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See detailConstitutive expression of tdTomato protein as a cytotoxicity and proliferation marker for space radiation biology
Chishti, Arif A.; Hellweg, Christine E.; Berger, Thomas et al

in Life Sciences in Space Research (2015), 4

The radiation risk assessment for long-term space missions requires knowledge on the biological effectiveness of different space radiation components, e.g. heavy ions, on the interaction of radiation and ... [more ▼]

The radiation risk assessment for long-term space missions requires knowledge on the biological effectiveness of different space radiation components, e.g. heavy ions, on the interaction of radiation and other space environmental factors such as microgravity, and on the physical and biological dose distribution in the human body. Space experiments and ground-based experiments at heavy ion accelerators require fast and reliable test systems with an easy readout for different endpoints. In order to determine the effect of different radiation qualities on cellular proliferation and the biological depth dose distribution after heavy ion exposure, a stable human cell line expressing a novel fluorescent protein was established and characterized. tdTomato, a red fluorescent protein of the new generation with fast maturation and high fluorescence intensity, was selected as reporter of cell proliferation. Human embryonic kidney (HEK/293) cells were stably transfected with a plasmid encoding tdTomato under the control of the constitutively active cytomegalovirus (CMV) promoter (ptdTomato-N1). The stably transfected cell line was named HEK-ptdTomato-N1 8. This cytotoxicity biosensor was tested by ionizing radiation (X-rays and accelerated heavy ions) exposure. As biological endpoints, the proliferation kinetics and the cell density reached 100 h after irradiation reflected by constitutive expression of the tdTomato were investigated. Both were reduced dose-dependently after radiation exposure. Finally, the cell line was used for biological weighting of heavy ions of different linear energy transfer (LET) as space-relevant radiation quality. The relative biological effectiveness of accelerated heavy ions in reducing cellular proliferation peaked at an LET of 91 keV/μm. The results of this study demonstrate that the HEK-ptdTomato-N1 reporter cell line can be used as a fast and reliable biosensor system for detection of cytotoxic damage caused by ionizing radiation. © 2015 The Committee on Space Research (COSPAR). [less ▲]

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See detailConstitutive Norms in the Design of Normative Multiagent Systems
Boella, Guido; van der Torre, Leon UL

in Computational Logic in Multi-Agent Systems, 6th International Workshop (CLIMA VI) (2006)

In this paper, we consider the design of normative multiagent systems composed of both constitutive and regulative norms. We analyze the properties of constitutive norms, in particular their lack of ... [more ▼]

In this paper, we consider the design of normative multiagent systems composed of both constitutive and regulative norms. We analyze the properties of constitutive norms, in particular their lack of reflexivity, and the trade-off between constitutive and regulative norms in the design of normative systems. As methodology we use the metaphor of describing social entities as agents and of attributing them mental attitudes. In this agent metaphor, regulative norms expressing obligations and permissions are modelled as goals of social entities, and constitutive norms expressing “counts-as” relations are their beliefs. [less ▲]

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See detailConstitutive suppressor of cytokine signaling 3 expression confers a growth advantage to a human melanoma cell line
Komyod, W.; Böhm, M.; Metze, D. et al

in Molecular Cancer Research (2007), 5(3), 271-81

The growth of melanocytes and many early stage melanoma cells can be inhibited by cytokines, whereas late stage melanoma cells have often been reported to be "multi-cytokine-resistant." Here, we analyzed ... [more ▼]

The growth of melanocytes and many early stage melanoma cells can be inhibited by cytokines, whereas late stage melanoma cells have often been reported to be "multi-cytokine-resistant." Here, we analyzed the melanoma cell line 1286, resistant towards the growth-inhibitory effects of interleukin 6 (IL-6), and oncostatin M (OSM), to better understand the mechanisms underlying cytokine resistance. Although the relevant receptors gp130 and OSMR are expressed at the cell surface of these cells, cytokine stimulation hardly led to the activation of Janus kinase 1 and signal transducer and activator of transcription (STAT)3 and STAT1. We found a high-level constitutive expression of suppressors of cytokine signaling 3 (SOCS3) that did not further increase after cytokine treatment. Importantly, upon suppression of SOCS3 by short interfering RNA, cells became susceptible towards OSM and IL-6: they showed an enhanced STAT3 phosphorylation and a dramatically increased STAT1 phosphorylation. Moreover, suppression of SOCS3 rendered 1286 cells sensitive to the antiproliferative action of IL-6 and OSM, but not of IFN-alpha. Interestingly, SOCS3-short interfering RNA treatment also increased the growth-inhibitory effect in cytokine-sensitive WM239 cells expressing SOCS3 in an inducible way. Thus, SOCS3 expression confers a growth advantage to these cell lines. Constitutive SOCS3 mRNA expression, although at lower levels than in 1286 cells, was found in nine additional human melanoma cell lines and in normal human melanocytes, although at the protein level, SOCS3 expression was marginal at best. However, in situ analysis of human melanoma specimens revealed SOCS3 immunoreactivity in 3 out of 10 samples, suggesting that in vivo SOCS3 may possibly play a role in IL-6 resistance in at least a fraction of tumors. [less ▲]

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See detailConstrained Bayesian Active Learning of Interference Channels in Cognitive Radio Networks
Tsakmalis, Anestis UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in IEEE Journal of Selected Topics in Signal Processing (2017)

In this paper, a sequential probing method for interference constraint learning is proposed to allow a centralized Cognitive Radio Network (CRN) accessing the frequency band of a Primary User (PU) in an ... [more ▼]

In this paper, a sequential probing method for interference constraint learning is proposed to allow a centralized Cognitive Radio Network (CRN) accessing the frequency band of a Primary User (PU) in an underlay cognitive scenario with a designed PU protection specification. The main idea is that the CRN probes the PU and subsequently eavesdrops the reverse PU link to acquire the binary ACK/NACK packet. This feedback indicates whether the probing-induced interference is harmful or not and can be used to learn the PU interference constraint. The cognitive part of this sequential probing process is the selection of the power levels of the Secondary Users (SUs) which aims to learn the PU interference constraint with a minimum number of probing attempts while setting a limit on the number of harmful probing-induced interference events or equivalently of NACK packet observations over a time window. This constrained design problem is studied within the Active Learning (AL) framework and an optimal solution is derived and implemented with a sophisticated, accurate and fast Bayesian Learning method, the Expectation Propagation (EP). The performance of this solution is also demonstrated through numerical simulations and compared with modified versions of AL techniques we developed in earlier work. [less ▲]

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See detailConstrained bayesian active learning of linear classifier
Tsakmalis, Anestis UL; Chatzinotas, Symeon UL; Ottersten, Björn UL

in 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (2018)

In this paper, an on-line interactive method is proposed for learning a linear classifier. This problem is studied within the Active Learning (AL) framework where the learning algorithm sequentially ... [more ▼]

In this paper, an on-line interactive method is proposed for learning a linear classifier. This problem is studied within the Active Learning (AL) framework where the learning algorithm sequentially chooses unlabelled training samples and requests their class labels from an oracle in order to learn the classifier with the least queries to the oracle possible. Additionally' a constraint is introduced into this interactive learning process which limits the percentage of the samples from one “unwanted” class under a certain threshold. An optimal AL solution is derived and implemented with a sophisticated, accurate and fast Bayesian Learning method, the Expectation Propagation (EP) and its performance is demonstrated through numerical simulations. [less ▲]

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See detailConstraining Dominant Shareholders' Self-Dealing: The Legal Framework in France, Germany, and Italy
Conac, Pierre-Henri UL; Enriques, Luca; Gelter, Martin

in European Company and Financial Law Review (2007), 4(4), 491

All jurisdictions supply corporations with legal tools to prevent or punish asset diversion by those, whether managers or dominant shareholders, who are in control. As previous research has shown, these ... [more ▼]

All jurisdictions supply corporations with legal tools to prevent or punish asset diversion by those, whether managers or dominant shareholders, who are in control. As previous research has shown, these rules, doctrines and remedies are far from uniform across jurisdictions, possibly leading to significant differences in the degree of investor protection they provide. Comparative research in this field is wrought with difficulty. It is tempting to compare corporate laws by taking one benchmark jurisdiction, typically the US, and to assess the quality of other corporate law systems depending on how much they replicate some prominent features. We take a different perspective and describe how three major continental European countries (France, Germany, and Italy) regulate dominant shareholders' self-dealing by looking at all the possible rules, doctrines and remedies available there. While the doctrines and remedies reviewed in this article are familiar enough to corporate lawyers and legal scholars from the respective countries, this is less true for many participants in the international discussion, which remains dominated by Anglophone legal scholars and economists. We suggest that some of these doctrines and remedies, namely the German prohibition against concealed distributions, the role of minority shareholders in the prosecution of abus de biens sociaux in France, and nullification suits in all three countries and especially in Germany and Italy, have not received the attention they deserve. [less ▲]

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See detailConstraint based modelling going multicellular
Martins Conde, Patricia UL; Sauter, Thomas UL; Pfau, Thomas UL

in Frontiers in Molecular Biosciences (2016), 3(3),

Constraint based modelling has seen applications in many microorganisms. For example, there are now established methods to determine potential genetic modifications and external interventions to increase ... [more ▼]

Constraint based modelling has seen applications in many microorganisms. For example, there are now established methods to determine potential genetic modifications and external interventions to increase the efficiency of microbial strains in chemical production pipelines. In addition, multiple models of multicellular organisms have been created including plants and humans. While initially the focus here was on modelling individual cell types of the multicellular organism, this focus recently started to switch. Models of microbial communities, as well as multitissue models of higher organisms have been constructed. These models thereby can include different parts of a plant, like root, stem or different tissue types in the same organ. Such models can elucidate details of the interplay between symbiotic organisms, as well as the concerted efforts of multiple tissues and can be applied to analyse the effects of drugs or mutations on a more systemic level. In this review we give an overview of the recent development of multi-tissue models using constraint based techniques and the methods employed when investigating these models. We further highlight advances in combining constraint based models with dynamic and regulatory information and give an overview of these types of hybrid or multi-level approaches. [less ▲]

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See detailA constraint system for a SML type error slicer
Rahli, Vincent UL; Wells, J. B.; Kamareddine, Fairouz

Report (2010)

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See detailA constraint-based modelling approach to metabolic dysfunction in Parkinson's disease
Mao, Longfei UL; Nicolae, Averina UL; Oliveira, Miguel UL et al

in Computational and Structural Biotechnology Journal (2015), 13

Abstract One of the hallmarks of sporadic Parkinson's disease is degeneration of dopaminergic neurons in the pars compacta of the substantia nigra. The aetiopathogenesis of this degeneration is still not ... [more ▼]

Abstract One of the hallmarks of sporadic Parkinson's disease is degeneration of dopaminergic neurons in the pars compacta of the substantia nigra. The aetiopathogenesis of this degeneration is still not fully understood, with dysfunction of many biochemical pathways in different subsystems suggested to be involved. Recent advances in constraint-based modelling approaches hold great potential to systematically examine the relative contribution of dysfunction in disparate pathways to dopaminergic neuronal degeneration, but few studies have employed these methods in Parkinson's disease research. Therefore, this review outlines a framework for future constraint-based modelling of dopaminergic neuronal metabolism to decipher the multi-factorial mechanisms underlying the neuronal pathology of Parkinson's disease. [less ▲]

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See detailConstraints on agency: Explorations of theory in everyday life
Valsiner, Jaan UL; Gruber, Craig; Clark, Matthew et al

Book published by Springer (2015)

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See detailConstraints on the upper crustal magma reservoir beneath Yellowstone Caldera inferred from lake-seiche induced strain observations
Luttrell, Karen; Mencin, David; Francis, Olivier UL et al

in Geophysical Research Letters (2013), 40(3), 501--506

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See detailThe Construal of National Identities within the Luxembourg Context
Murdock, Elke UL; Ferring, Dieter UL

Scientific Conference (2012, July 19)

We live in an increasingly mobile world. In line with the conference’s motto of “Nurturing Diversity for Sustainable Development” the current paper aims to make a contribution to the understanding of ... [more ▼]

We live in an increasingly mobile world. In line with the conference’s motto of “Nurturing Diversity for Sustainable Development” the current paper aims to make a contribution to the understanding of individual national identity construal processes within a multi-national environment. Understanding these processes may facilitate the fostering of the acceptance of culturally heterogeneous identities. Starting point for this on-going, empirical study is Luxembourg, a country with approx. ½ m inhabitants, a foreign population of 43% (increasing to over 60% in the capital) and three officially recognized languages which are spoken throughout the country. Luxembourg can be viewed as a “natural laboratory.” Given its size, population mix and closeness of borders there is ample opportunity for “second culture exposure.” How is national identity construed within such a diverse context? Is second culture exposure experienced as an enrichment or a threat? Three groups, recruited on power analytical considerations and differentiated by their length of stay in Luxembourg (native residents, Luxembourgers with migrant background and sojourners) are analyzed regarding their national identity construal process along the primordialist – situationalist spectrum. Identity Structure Analysis (ISA) is used as theoretical framework and methodological tool. Given the multi-national context, it is assumed that situationalists will be in the majority across all three groups. However, given the developmental primacy of primordialism, some persistence of the primordial orientation is expected. Bicultural orientation is also assessed. Within this context, three questions are examined: Firstly, do individuals consider it possible to have more than one national identity? Secondly, if this is the case, are these national identities kept separate or integrated (cultural distance) and thirdly is this experienced harmoniously or as a source of conflict. Research on biculturalism and ISA are linked in the assumption that those individuals who gravitate towards situationalism will also consider it possible to have a bicultural identity. In a third step, the role of dispositional factors (Big FIVE personality variables) and demographic/ biographic variables will be examined as it is anticipated that these influence how bicultural identity is expressed (separated vs. integrated) and experienced (conflicted vs. harmonious). The study explores to what extent dispositional and demographic factors determine how second culture is experienced – whether diversity is experienced as a source of enrichment and joy or threat. [less ▲]

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See detailConstruçao de rupturas sociais: pobreza e exclusao social na perspectiva das sociologias
Leandro, M. E.; Baumann, Michèle UL

in Da integracao social. Laços Familiares e Sociais. (2011)

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See detailA construção social da infância: idade, gênero e identidades infantis.
Ramos, Anne Carolina UL

in Revista Feminismos (2013), 1(3),

As a social construction, childhood is an arbitrary fragmentation based on a universally-occurring phenomenon that is part of the natural cycle of life. Awareness of the particular nature of childhood and ... [more ▼]

As a social construction, childhood is an arbitrary fragmentation based on a universally-occurring phenomenon that is part of the natural cycle of life. Awareness of the particular nature of childhood and the birth of a “feeling of childhood” (Ariès, 1981) would emerge by way of a growing distinction between the world of children and that of adults, identified not only by biological age, but also by a series of cultural interventions made in relation to children. Such interventions will also be strongly influenced by a gendering of childhood. This article seeks to discuss the social construction of childhood, analyzing how age and gender are important phenomena in the formation of children's identities. It shows that children are not mere potential beings, but active participants in the construction of their social worlds. [less ▲]

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See detailConstruct validity of complex problem solving: A comprehensive view on different facets of intelligence and school grades
Kretzschmar, André UL; Neubert, Jonas UL; Wüstenberg, Sascha UL et al

in Intelligence (2016), 54

Although Complex Problem Solving (CPS) has attracted increasing amounts of attention in recent years (e.g., PISA study), the role of CPS in the nomological network of intelligence is controversial. The ... [more ▼]

Although Complex Problem Solving (CPS) has attracted increasing amounts of attention in recent years (e.g., PISA study), the role of CPS in the nomological network of intelligence is controversial. The question of whether CPS is a distinct construct is as old as CPS research itself, but previous studies have had specific shortcomings when addressing the question of whether CPS is a separable or independent construct. The aim of the present study was, therefore, to combine the advantages of previous studies to facilitate a less biased view of the relation between CPS and established intelligence constructs. A sample of 227 German university students worked on a comprehensive measure of intelligence (Berlin Intelligence Structure test) and two CPS assessment tools (MicroDYN and MicroFIN). Furthermore, final school grades (GPA) served as an external criterion. We applied confirmatory factor analyses and structural equation modeling to investigate the relation between CPS and established intelligence constructs on the basis of different psychometric approaches (i.e., first-order model, nested factor model). Moreover, we examined the incremental validity of CPS in explaining GPA beyond established intelligence constructs. Results indicate that CPS represents unique variance that is not accounted for by established intelligence constructs. The incremental validity of CPS was found only when a commonly used narrow operationalization of intelligence was applied (i.e., figural reasoning) but not when a broad operationalization was applied. [less ▲]

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See detailConstruct validity of the Anxiety Sensitivity Index-3 in clinical samples
Kemper, Christoph UL; Lutz, J.; Bähr, T. et al

in Assessment (2012), 19(1), 89-100

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See detailConstructing a national discourse or encouraging the intercultural dialogue: the case of two museums in Luxembourg
Schall, Céline UL

Scientific Conference (2012)

The notion of identity is often linked to the museum, as we can see in the museology literature (Thatcher, 2005 and 2012, Gob, 2010; Mairesse, 2011, Nemery, Rautenberg, Thuriot, 2008, etc.), during ... [more ▼]

The notion of identity is often linked to the museum, as we can see in the museology literature (Thatcher, 2005 and 2012, Gob, 2010; Mairesse, 2011, Nemery, Rautenberg, Thuriot, 2008, etc.), during previous Eunamus symposia or during this conference itself. The link between identity and museum is sometimes poorly defined and it also tends to evolve over time. For example, the national heritage was first used to build the nation, while showing in what sense the other is "other." Since the 70s and 80s, by contrast, the increased value attached to the cultures of the different communities has been put forward in order to address all citizens (Caillet in Ministry of Culture, 2009). Finally, since the turn of the millennium, the idea of ​​a "forum museum" which includes all communities has gained momentum, especially given the current European economic and social perils that threaten social cohesion within individual countries as well as Europe as a whole (Ministry of Culture, 2009). But in the present time of crises, in a multicultural country like Luxembourg, what are the uses of the identity discourses in national museums? Here, we would like to present, the case of two of the 8 National Museums of Luxembourg. 1) First, we will focus briefly on the link between identity and history museums in the context of Luxembourg. 2) Next, we will look at the permanent exhibition of these museums, which both speak about the Second World War but represent two very different cases of identity appropriation of the historical discourse. We will also study their plans for the future (two renovation projects currently underway). 3) Finally, we will consider the limitations and strengths of the two approaches and what their roles might be in the future, in particular when it comes to ensuring greater cohesion between nationalities living in Luxembourg and in Europe. [less ▲]

Detailed reference viewed: 67 (7 UL)