66 research outputs found
Measure of Node Similarity in Multilayer Networks
The weight of links in a network is often related to the similarity of the
nodes. Here, we introduce a simple tunable measure for analysing the similarity
of nodes across different link weights. In particular, we use the measure to
analyze homophily in a group of 659 freshman students at a large university.
Our analysis is based on data obtained using smartphones equipped with custom
data collection software, complemented by questionnaire-based data. The network
of social contacts is represented as a weighted multilayer network constructed
from different channels of telecommunication as well as data on face-to-face
contacts. We find that even strongly connected individuals are not more similar
with respect to basic personality traits than randomly chosen pairs of
individuals. In contrast, several socio-demographics variables have a
significant degree of similarity. We further observe that similarity might be
present in one layer of the multilayer network and simultaneously be absent in
the other layers. For a variable such as gender, our measure reveals a
transition from similarity between nodes connected with links of relatively low
weight to dis-similarity for the nodes connected by the strongest links. We
finally analyze the overlap between layers in the network for different levels
of acquaintanceships.Comment: 12 pages, 4 figure
Bailouts in a common market: a strategic approach
Governments in the EU grant Rescue and Restructure Subsidies to bail out ailing firms. In an international asymmetric Cournot duopoly we study effects of such subsidies on market structure and welfare. We adopt a common market setting, where consumers from the two countries form one market. We show that the subsidy is positive also when it fails to prevent the exit. The reason is a strategic effect, which forces the more efficient firm to make additional cost-reducing effort. When the exit is prevented, allocative and productive efficiencies are lower and the only gaining player is the rescued firm
BRCA1-regulated RRM2 expression protects glioblastoma cells from endogenous replication stress and promotes tumorigenicity
Oncogene-evoked replication stress (RS) fuels genomic instability in diverse cancer types. Here we report that BRCA1, traditionally regarded a tumour suppressor, plays an unexpected tumour-promoting role in glioblastoma (GBM), safeguarding a protective response to supraphysiological RS levels. Higher BRCA1 positivity is associated with shorter survival of glioma patients and the abrogation of BRCA1 function in GBM enhances RS, DNA damage (DD) accumulation and impairs tumour growth. Mechanistically, we identify a novel role of BRCA1 as a transcriptional co-activator of RRM2 (catalytic subunit of ribonucleotide reductase), whereby BRCA1-mediated RRM2 expression protects GBM cells from endogenous RS, DD and apoptosis. Notably, we show that treatment with a RRM2 inhibitor triapine reproduces the BRCA1-depletion GBM-repressive phenotypes and sensitizes GBM cells to PARP inhibition. We propose that GBM cells are addicted to the RS-protective role of the BRCA1-RRM2 axis, targeting of which may represent a novel paradigm for therapeutic intervention in GBM
Gauge cooling for the singular-drift problem in the complex Langevin method — a test in Random Matrix Theory for finite density QCD
The association of DNA damage response and nucleotide level modulation with the antibacterial mechanism of the anti-folate drug Trimethoprim
Understanding the interplay between social and spatial behaviour
According to personality psychology, personality traits determine many aspects of human behaviour. However, validating this insight in large groups has been challenging so far, due to the scarcity of multi-channel data. Here, we focus on the relationship between mobility and social behaviour by analysing trajectories and mobile phone interactions of ∼1000 individuals from two high-resolution longitudinal datasets. We identify a connection between the way in which individuals explore new resources and exploit known assets in the social and spatial spheres. We show that different individuals balance the exploration-exploitation trade-off in different ways and we explain part of the variability in the data by the big five personality traits. We point out that, in both realms, extraversion correlates with the attitude towards exploration and routine diversity, while neuroticism and openness account for the tendency to evolve routine over long time-scales. We find no evidence for the existence of classes of individuals across the spatio-social domains. Our results bridge the fields of human geography, sociology and personality psychology and can help improve current models of mobility and tie formation
Essays on the determination and formation of prices in European crude oil markets
Defence date: 18 June 1993Examining board: Birgit Grodal ; Ronald Harstad ; Stephen Martin ; Louis Phlips (supervisor) ; Jacques-François Thisse ; Antonio VillarFirst made available online on 19 November 2012
Bargaining and efficiency in a speculative forward market
Digitised version produced by the EUI Library and made available online in 2020
A Squeezer Round the Corner? Self-Regulation and Forward Markets.
Squeezes are registered in the forward market for Brent crude oil. The squeezer accumulates forward contracts and creates artificial demand. This causes the price to surge and introduces uncertainty about the market outcome. Squeezes therefore render the market institution less palatable to other market participants. Producers may have a longterm interest in keeping market clearing smooth, e.g., by supplying stocks to squeezed traders. The extent to which such self-regulation should be carried out is analyzed in the context of a repeated game. Unless the probability of a squeeze is very small, self-regulation should be possible. Copyright 1997 by Royal Economic Society.
Oil futures and strategic stocks at sea
Digitised version produced by the EUI Library and made available online in 2020
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