3,109 research outputs found
Le rôle de la bibliothèque publique dans l'intégration des populations immigrées
Ce travail présente deux finalités : en premier lieu, il s’agit de livrer à la Bibliothèque publique et scolaire d’Yverdon-les-Bains (BPY) une réflexion théorique sur le rôle des bibliothèques publiques dans l’intégration des populations immigrées. En deuxième lieu, il s’agit de lui proposer des actions concrètes pouvant être mises en oeuvre à la BPY dans le but de favoriser cette intégration. Cette étude doit pouvoir être une source d’information intéressante et pertinente pour les bibliothèques publiques en général. Ce travail est réalisé à l’intention de la BPY. L’institution organise régulièrement des actions de natures diverses et fait actuellement partie intégrante de la dynamique culturelle de la ville, ce qui lui apporte légitimité et visibilité. Le potentiel social et « troisième lieu » des bibliothèques est une importante source d’intérêt de de motivation. En outre, je suis sensible au sujet de l’immigration et du processus d’intégration qui en découle. C’est de l’association de ces deux intérêts apparemment distincts que sont nés le sujet et la problématique de mon travail. Le contexte environnemental, quant à lui, n’a pas été choisi au hasard ; je suis native d’Yverdon-les-Bains et sa citoyenne depuis toujours. J’évolue ainsi en territoire connu, sensibilisée, grâce à mes connaissances et amis, aux réalités humaines consécutives à l’état d’immigré. La base de ce travail est une réflexion théorique sur le rôle des bibliothèques dans l’intégration des immigrés, à partir de laquelle sont produites des propositions d’actions concrètes, adaptées à la BPY, rendues sous forme de fiches techniques. Il s’agit également d’une contribution documentaire, car cette étude vise à être mise à disposition des bibliothèques publiques intéressées qui pourront les contextualiser
Enzyme activity below the dynamical transition at 220 K
Enzyme activity requires the activation of anharmonic motions, such as jumps between potential energy wells. However, in general, the forms and time scales of the functionally important anharmonic dynamics coupled to motion along the reaction coordinate remain to be determined. In particular, the question arises whether the temperature-dependent dynamical transition from harmonic to anharmonic motion in proteins, which has been observed experimentally and using molecular dynamics simulation, involves the activation of motions required for enzyme function. Here we present parallel measurements of the activity and dynamics of a cryosolution of glutamate dehydrogenase as a function of temperature. The dynamical atomic fluctuations faster than ~100 ps were determined using neutron scattering. The results show that the enzyme remains active below the dynamical transition observed at ~220 K, i.e., at temperatures where no anharmonic motion is detected. Furthermore, the activity shows no significant deviation from Arrhenius behavior down to 190 K. The results indicate that the observed transition in the enzyme's dynamics is decoupled from the rate-limiting step along the reaction coordinate
New aesthetic, new anxieties
The New Aesthetic was a design concept and netculture phenomenon
launched into the world by London designer James Bridle in 2011. It
continues to attract the attention of media art, and throw up
associations to a variety of situated practices, including speculative
design, net criticism, hacking, free and open source software
development, locative media, sustainable hardware and so on. In this book we consider the New Aesthetic: as an opportunity to rethink
the relations between these contexts in the emergent episteme of
computationality. There is a desperate need to confront the political
pressures of neoliberalism manifested in these infrastructures.
Indeed, these are risky, dangerous and problematic times; a period
when critique should thrive. But here we need to forge new alliances,
invent and discover problems of the common that nevertheless do not
eliminate the fundamental differences in this ecology of practices. In
this book, perhaps provocatively, we believe a great deal could be
learned from the development of the New Aesthetic not only as a mood,
but as a topic and fix for collective feeling, that temporarily
mobilizes networks. Is it possible to sustain and capture these
atmospheres of debate and discussion beyond knee-jerk reactions and
opportunistic self-promotion? These are crucial questions that the New
Aesthetic invites us to consider, if only to keep a critical network
culture in place
The Land O\u27 Romance
Clovers and castles background with man in oval picture framehttps://scholarsjunction.msstate.edu/cht-sheet-music/11491/thumbnail.jp
De-Icing Soil Impacts, Spring 2020
De-Icing Impacts on the Danforth Campus, Spring 2020. Poster and presentation on de-icing impacts on Danforth Campus, Washington University in St. Louis, Sustainability Exchange, Spring 2020. Faculty Mentor: Dr. Avni Solank
Signatures of a gearwheel quantum spin liquid in a spin- pyrochlore molybdate Heisenberg antiferromagnet
We theoretically investigate the low-temperature phase of the recently
synthesized LuMoON material, an extraordinarily rare
realization of a three-dimensional pyrochlore Heisenberg
antiferromagnet in which Mo are the magnetic species. Despite a
Curie-Weiss temperature () of K, experiments have
found no signature of magnetic ordering spin freezing down to
K. Using density functional theory, we find that the compound
is well described by a Heisenberg model with exchange parameters up to third
nearest neighbors. The analysis of this model via the pseudofermion functional
renormalization group method reveals paramagnetic behavior down to a
temperature of at least , in agreement with the
experimental findings hinting at a possible three-dimensional quantum spin
liquid. The spin susceptibility profile in reciprocal space shows
momentum-dependent features forming a "gearwheel" pattern, characterizing what
may be viewed as a molten version of a chiral noncoplanar incommensurate spiral
order under the action of quantum fluctuations. Our calculated reciprocal space
susceptibility maps provide benchmarks for future neutron scattering
experiments on single crystals of LuMoON.Comment: Published version. Main paper (6 pages, 3 figures) + Supplemental
Material (4 pages, 3 figures, 1 table
Recommended from our members
New insight from CryoSat-2 sea ice thickness for sea ice modelling
Estimates of Arctic sea ice thickness are available from the CryoSat-2 (CS2) radar altimetry mission during ice growth seasons since 2010. We derive the sub-grid scale ice thickness distribution (ITD) with respect to 5 ice thickness categories used in a sea ice component (CICE) of climate simulations. This allows us to initialize the ITD in stand-alone simulations with CICE and to verify the simulated cycle of ice thickness. We find that a default CICE simulation strongly underestimates ice thickness, despite reproducing the inter-annual variability of summer sea ice extent. We can identify the underestimation of winter ice growth as being responsible and show that increasing the ice conductive flux for lower temperatures (bubbly brine scheme) and accounting for the loss of drifting snow results in the simulated sea ice growth being more realistic. Sensitivity studies provide insight into the impact of initial and atmospheric conditions and, thus, on the role of positive and negative feedback processes. During summer, atmospheric conditions are responsible for 50% of September sea ice thickness variability through the positive sea ice and melt pond albedo feedback. However, atmospheric winter conditions have little impact on winter ice growth due to the dominating negative conductive feedback process: the thinner the ice and snow in autumn, the stronger the ice growth in winter. We conclude that the fate of Arctic summer sea ice is largely controlled by atmospheric conditions during the melting season rather than by winter temperature. Our optimal model configuration does not only improve the simulated sea ice thickness, but also summer sea ice concentration, melt pond fraction, and length of the melt season. It is the first time CS2 sea ice thickness data have been applied successfully to improve sea ice model physics
The Ultraviolet Radiation Environment Around M dwarf Exoplanet Host Stars
The spectral and temporal behavior of exoplanet host stars is a critical
input to models of the chemistry and evolution of planetary atmospheres. At
present, little observational or theoretical basis exists for understanding the
ultraviolet spectra of M dwarfs, despite their critical importance to
predicting and interpreting the spectra of potentially habitable planets as
they are obtained in the coming decades. Using observations from the Hubble
Space Telescope, we present a study of the UV radiation fields around nearby M
dwarf planet hosts that covers both FUV and NUV wavelengths. The combined
FUV+NUV spectra are publically available in machine-readable format. We find
that all six exoplanet host stars in our sample (GJ 581, GJ 876, GJ 436, GJ
832, GJ 667C, and GJ 1214) exhibit some level of chromospheric and transition
region UV emission. No "UV quiet" M dwarfs are observed. The bright stellar
Ly-alpha emission lines are reconstructed, and we find that the Ly-alpha line
fluxes comprise ~37-75% of the total 1150-3100A flux from most M dwarfs; >
10^{3} times the solar value. The F(FUV)/F(NUV) flux ratio, a driver for
abiotic production of the suggested biomarkers O2 and O3, is shown to be ~0.5-3
for all M dwarfs in our sample, > 10^{3} times the solar ratio. For the four
stars with moderate signal-to-noise COS time-resolved spectra, we find UV
emission line variability with amplitudes of 50-500% on 10^{2} - 10^{3} s
timescales. Finally, we observe relatively bright H2 fluorescent emission from
four of the M dwarf exoplanetary systems (GJ 581, GJ 876, GJ 436, and GJ 832).
Additional modeling work is needed to differentiate between a stellar
photospheric or possible exoplanetary origin for the hot (T(H2) \approx
2000-4000 K) molecular gas observed in these objects.Comment: ApJ, accepted. 16 pages, 10 figures. On-line data at:
http://cos.colorado.edu/~kevinf/muscles.htm
Genetic analysis for mastitis resistance and milk somatic cell score in French Lacaune dairy sheep
Genetic analysis for mastitis resistance was studied from two data sets. Firstly, risk factors for different mastitis traits, i.e. culling due to clinical or chronic mastitis and subclinical mastitis predicted from somatic cell count (SCC), were explored using data from 957 first lactation Lacaune ewes of an experimental INRA flock composed of two divergent lines for milk yield. Secondly, genetic parameters for SCC were estimated from 5 272 first lactation Lacaune ewes recorded among 38 flocks, using an animal model. In the experimental flock, the frequency of culling due to clinical mastitis (5%) was lower than that of subclinical mastitis (10%) predicted from SCC. Predicted subclinical mastitis was unfavourably associated with the milk yield level. Such an antagonism was not detected for clinical mastitis, which could result, to some extent, from its low frequency or from the limited amount of data. In practice, however, selection for mastitis resistance could be limited in a first approach to selection against subclinical mastitis using SCC. The heritability estimate of SCC was 0.15 for the lactation mean trait and varied from 0.04 to 0.12 from the first to the fifth test-day. The genetic correlation between lactation SCC and milk yield was slightly positive (0.15) but showed a strong evolution during lactation, i.e. from favourable (-0.48) to antagonistic (0.27). On a lactation basis, our results suggest that selection for mastitis resistance based on SCC is feasible. Patterns for genetic parameters within first lactation, however, require further confirmation and investigation
Connecting the Dots: Analyzing Synthetic Observations of Star-Forming Clumps in Molecular Clouds
In this paper, we investigate the extent to which observations of molecular
clouds can correctly identify and measure star-forming clumps. We produced a
synthetic column density map and a synthetic spectral-line data cube from the
simulated collapse of a 5000 M molecular cloud. By correlating the
clumps found in the simulation to those found in the synthetic observations,
clump masses derived from spectral-line data cubes were found to be quite close
to the true physical properties of the clumps. We also find that the `observed'
clump mass function derived from the column density map is shifted by a factor
of ~ 3 higher than the true clump mass function, due to projection of
low-density material along the line of sight. Alves et al. (2007) first
proposed that a shift of a clump mass function to higher masses by a factor of
3 can be attributed to a star formation efficiency of 30 %. Our results
indicate that this finding may instead be due to an overestimate of clump
masses determined from column density observations.Comment: 8 pages, 7 figures, Accepted for publication in the Astrophysical
Journa
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