2,501 research outputs found
Reconstructing Deconstruction: High-Velocity Cloud Distance Through Disruption Morphology
We present Arecibo L-band Feed Array 21-cm observations of a sub-complex of
HVCs at the tip of the Anti-Center Complex. These observations show
morphological details that point to interaction with the ambient halo medium
and differential drag within the cloud sub-complex. We develop a new technique
for measuring cloud distances, which relies upon these observed morphological
and kinematic characteristics, and show that it is consistent with H-alpha
distances. These results are consistent with distances to HVCs and halo
densities derived from models in which HVCs are formed from cooling halo gas.Comment: 8 pages, 2 figures, 1 tabe, Accepted to Ap
Evidence for Jahn-Teller distortions at the antiferromagnetic transition in LaTiO
LaTiO is known as Mott-insulator which orders antiferromagnetically at
K. We report on results of thermal expansion and temperature
dependent x-ray diffraction together with measurements of the heat capacity,
electrical transport measurements, and optical spectroscopy in untwinned single
crystals. At significant structural changes appear, which are
volume conserving. Concomitant anomalies are also observed in the
dc-resistivity, in bulk modulus, and optical reflectivity spectra. We interpret
these experimental observations as evidence of orbital order.Comment: 4 pages, 4 figures; published in Phys. Rev. Lett. 91, 066403 (2003
Measurements of O3</sub>, NO<sub>2</sub> and BrO at the Kaashidhoo Climate Observatory (KCO) during the INDOEX (INDian Ocean EXperiment) Campaign using ground based DOAS (Differential Optical Absorption Spectroscopy) and satellite based GOME (Global Ozone Monitoring Experiment) data
International audienceThe INDian Ocean EXperiment (INDOEX) was an international, multi-platform field campaign to measure long-range transport of air masses from South and South-East-(SE) Asia towards the Indian Ocean. During the dry monsoon season between January and March 1999, local measurements were carried out from ground based platforms and were compared with satellite based data. The objective of this study was to characterise stratospheric and tropospheric trace gas amounts in the equatorial region, and to investigate the impact of air pollution at this remote site. For the characterisation of the chemical composition of the outflow from the S-SE-Asian region, we performed ground based dual-axis-DOAS (Differential Optical Absorption Spectroscopy) measurements at the KCO (Kaashidhoo Climate Observatory) in the Maldives (5.0Ā° N, 73.5Ā° E). The ground based dual-axis-DOAS measurements were conducted using two different observation modes (off-axis and zenith-sky). This technique allows the separation of the tropospheric and stratospheric columns for different trace gases like O3 and NO2. These dual-axis DOAS data were compared with O3-sonde measurements performed at KCO and satellite based GOME (Global Ozone Measuring Experiment) data during the intensive measuring phase of the INDOEX campaign in February and March 1999. From GOME observations, tropospheric and stratospheric columns for O3 and NO2 were retrieved. In addition, the analysis of the O3-sonde measurements allowed the determination of the tropospheric O3 amount. The comparison shows that the results of all three measurement systems agree within their error limits. During the INDOEX campaign, background conditions were observed most of the time, but in a single case an increase of tropospheric NO2 during a short pollution event was observed and the impact on the vertical columns was calculated. In the GOME measurements, evidence was found for large tropospheric contributions to the BrO budget, probably located in the free troposphere and present throughout the year. The latter has been investigated by the comparison of satellite pixels influenced by high and low cloud conditions based on GOME data which allows the determination of the detection limit of tropospheric BrO columns
A hashtag worth a thousand words: Discursive strategies around #JeNeSuisPasCharlie after the 2015 Charlie Hebdo shooting
Following a shooting attack by two self-proclaimed Islamist gunmen at the offices of French satirical weekly Charlie Hebdo on 7 January 2015, there emerged the hashtag #JeSuisCharlie on Twitter as an expression of solidarity and support for the magazineās right to free speech. Almost simultaneously, however, there was also #JeNeSuisPasCharlie explicitly countering the former, affirmative hashtag. Based on a multimethod analysis of 74,047 tweets containing #JeNeSuisPasCharlie posted between 7 and 11 January, this article reveals that users of the hashtag under study employed various discursive strategies and tactics to challenge the mainstream framing of the shooting as the universal value of freedom of expression being threatened by religious extremism, while protecting themselves from the risk of being viewed as disrespecting victims or endorsing the violence committed. The significance of this study is twofold. First, it extends the literature on strategic speech acts by examining how such acts take place in a social media context. Second, it highlights the need for a multidimensional and reflective methodology when dealing with data mined from social media
Coordination via Interaction Constraints I: Local Logic
Wegner describes coordination as constrained interaction. We take this
approach literally and define a coordination model based on interaction
constraints and partial, iterative and interactive constraint satisfaction. Our
model captures behaviour described in terms of synchronisation and data flow
constraints, plus various modes of interaction with the outside world provided
by external constraint symbols, on-the-fly constraint generation, and
coordination variables. Underlying our approach is an engine performing
(partial) constraint satisfaction of the sets of constraints. Our model extends
previous work on three counts: firstly, a more advanced notion of external
interaction is offered; secondly, our approach enables local satisfaction of
constraints with appropriate partial solutions, avoiding global synchronisation
over the entire constraints set; and, as a consequence, constraint satisfaction
can finally occur concurrently, and multiple parts of a set of constraints can
be solved and interact with the outside world in an asynchronous manner, unless
synchronisation is required by the constraints. This paper describes the
underlying logic, which enables a notion of local solution, and relates this
logic to the more global approach of our previous work based on classical
logic
Banks' risk assessment of Swedish SMEs
Building on the literatures on asymmetric information and risk taking, this paper applies conjoint experiments to investigate lending officers' probabilities of supporting credit to established or existing SMEs. Using a sample of 114 Swedish lending officers, we test hypotheses concerning how information on the borrower's ability to repay the loan; alignment of risk preferences; and risk sharing affect their willingness to grant credit. Results suggest that features that reduce the risk to the bank and shift the risk to the borrower have the largest impact. The paper highlights the interaction between factors that influence the credit decision. Implications for SMEs, banks and research are discussed
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