4,484 research outputs found
Exclusive diffractive Higgs and jet production at the LHC
The implementation of exclusive diffractive production of Higgs boson and
dijets in the FPMC (Forward Physics Monte Carlo) framework is presented
following the models by Khoze, Martin, Ryskin and Cudell, Dechambre, Hernandez
and Ivanov. The predictions of the models are compared to the CDF measurement
of exclusive jets and the uncertainties on the Higgs boson and jet production
cross sections at the LHC are discussed.Comment: Proceedings of the DIS 2010 workshop, Florence, Ital
Limit of Spin Squeezing in Finite Temperature Bose-Einstein Condensates
We show that, at finite temperature, the maximum spin squeezing achievable
using interactions in Bose-Einstein condensates has a finite limit when the
atom number at fixed density and interaction strength. We
calculate the limit of the squeezing parameter for a spatially homogeneous
system and show that it is bounded from above by the initial non-condensed
fraction.Comment: 4 pages, 4 figure
Pulmonary pressures and outcome in primary mitral regurgitation. Paradigm shift from Rung to Ladder
Peer reviewe
Exhibiting connections, connecting exhibitions: constructing trans-Pacific relationships through museum displays in Oceania (2006-2016)
This research explores the correlation between exhibitions and networks in the context
of the 21st century Pacific. Firstly, exhibitions are envisioned as relational and
connective practices that trigger interactions through their making. Secondly,
exhibition-‐products are regarded as the result of these relationships, which bring
together a wide range of agents including makers, things, spaces and epistemologies.
Applying the Actor-‐Network-‐Theory to the field of exhibition studies, this thesis follows
the path of six trans-‐Pacific museum displays. These case studies were developed
between 2006 and 2016 by three major institutions of Oceania, located in Aotearoa
New Zealand (Auckland Museum), Hawai‘i (Bernice Pauahi Bishop Museum) and Taiwan
(Kaohsiung Museum of Fine Arts).
After a theoretical and methodological introduction, Chapter 2 dwells on the history of
the institutions included in this research and pieces together the genealogical grounds
for each exhibition case study. Short-‐term exhibitions and their capacity to open new
museum routes are explored in Chapter 3. Long-‐term displays and the musealisation of
temporary pathways are presented in Chapter 4. While reassembling the trajectories of
each exhibition in Chapter 3 and 4 and connecting their genealogies, this study
examines the existence of parallels, translations and echoes amongst the case studies in
Chapter 5. Chapter 6 further emphasises these relationships and equally dwells on the
limitations and impacts of connective narratives by analysing the Pacific maps displayed
in these trans-‐Pacific exhibitions.
By and large, this research explores the increasing development of a trans-‐Pacific
culture of display in Oceania, which is examined through the lens of exhibitions
developed and presented in this region at the dawn of the 21st century
Shi arrangements and low elements in Coxeter groups
Given an arbitrary Coxeter system and a nonnegative integer , the
-Shi arrangement of is a subarrangement of the Coxeter hyperplane
arrangement of . The classical Shi arrangement () was introduced in
the case of affine Weyl groups by Shi to study Kazhdan-Lusztig cells for .
As two key results, Shi showed that each region of the Shi arrangement contains
exactly one element of minimal length in and that the union of their
inverses form a convex subset of the Coxeter complex. The set of -low
elements in were introduced to study the word problem of the corresponding
Artin-Tits (braid) group and they turn out to produce automata to study the
combinatorics of reduced words in .
In this article, we generalize and extend Shi's results to any Coxeter system
for any : (1) the set of minimal length elements of the regions in a -Shi
arrangement is precisely the set of -low elements, settling a conjecture of
the first and third authors in this case; (2) the union of the inverses of the
(-)low elements form a convex subset in the Coxeter complex, settling a
conjecture by the third author, Nadeau and Williams.Comment: 41 pages, 7 figure
Rapic project: toward a new generation of inexpensive heat exchanger-reactors for process intensification
Process intensification (PI) in chemical production is a major concern of chemical manufacturers. This alternative technology involves transposing syntheses into continuous plug flow reactors with process intensification, leading to a multifunctional heat exchanger-reactor. In this context, the RAPIC R&D project aims to develop an innovative low-cost component (in the 10 kg/hour range). This project deals with the design from the local to the global scale and with testing, from elementary mock-ups to pilot scale. The present paper gives a detailed description of this research project and presents the main results on specification and definition of the reaction channel and the first simple mock-ups
Eye movements in response to different cognitive activities measured by eyetracking: a prospective study on some of the neurolinguistics programming theories
The eyes are in constant movement to optimize the interpretation of the visual scene by the brain. Eye movements are controlled by complex neural networks that interact with the rest of the brain. The direction of our eye movements could thus be influenced by our cognitive activity (imagination, internal dialogue, memory, etc.). A given cognitive activity could then cause the gaze to move in a specific direction (a brief movement that would be instinctive and unconscious).
Neuro Linguistic Programming (NLP), which was developed in the 1970s by Richard Bandler and John Grinder (psychologist and linguist respectively), issued a comprehensive theory associating gaze directions with specific mental tasks. According to this theory, depending on the visual path observed, one could go back to the participant's thoughts and cognitive processes. Although NLP is widely used in many disciplines (communication, psychology, psychotherapy, marketing, etc), to date, few scientific studies have examined the validity of this theory.
Using eye tracking, this study explores one of the hypotheses of this theory, which is one of the pillars of NLP on visual language. We created a protocol based on a series of questions of different types (supposed to engage different brain areas) and we recorded by eye tracking the gaze movements at the end of each question while the participants were thinking and elaborating on the answer. Our results show that 1) complex questions elicit significantly more eye movements than control questions that necessitate little reflection, 2) the movements are not random but are oriented in selected directions, according to the different question types, 3) the orientations observed are not those predicted by the NLP theory.
This pilot experiment paves the way for further investigations to decipher the close links between eye movements and neural network activities in the brain
Eph:ephrin-B1 forward signaling controls fasciculation of sensory and motor axons
AbstractAxon fasciculation is one of the processes controlling topographic innervation during embryonic development. While axon guidance steers extending axons in the accurate direction, axon fasciculation allows sets of co-extending axons to grow in tight bundles. The Eph:ephrin family has been involved both in axon guidance and fasciculation, yet it remains unclear how these two distinct types of responses are elicited. Herein we have characterized the role of ephrin-B1, a member of the ephrinB family in sensory and motor innervation of the limb. We show that ephrin-B1 is expressed in sensory axons and in the limb bud mesenchyme while EphB2 is expressed in motor and sensory axons. Loss of ephrin-B1 had no impact on the accurate dorso-ventral innervation of the limb by motor axons, yet EfnB1 mutants exhibited decreased fasciculation of peripheral motor and sensory nerves. Using tissue-specific excision of EfnB1 and in vitro experiments, we demonstrate that ephrin-B1 controls fasciculation of axons via a surround repulsion mechanism involving growth cone collapse of EphB2-expressing axons. Altogether, our results highlight the complex role of Eph:ephrin signaling in the development of the sensory-motor circuit innervating the limb
Chemical signatures of a warped protoplanetary disc
Circumstellar discs may become warped or broken into distinct planes if there
is a stellar or planetary companion with an orbit that is misaligned with
respect to the disc. There is mounting observational evidence for
protoplanetary discs with misaligned inner discs and warps that may be caused
by such interactions with a previously undetected companion, giving us a
tantalising indication of possible planets forming there. Hydrodynamical and
radiative transfer models indicate that the temperature varies azimuthally in
warped discs due to the variable angle at which the disc surface faces the star
and this impacts the disc chemistry. We perform chemical modelling based on a
hydrodynamical model of a protoplanetary disc with an embedded planet orbiting
at a 12 inclination to the disc. Even for this small misalignment,
abundances of species including CO and HCO vary azimuthally and this
results in detectable azimuthal variations in submillimetre line emission.
Azimuthal variations in line emission may therefore indicate the presence of an
unseen embedded companion. Nonaxisymmetric chemical abundances should be
considered when interpreting molecular line maps of warped or shadowed
protoplanetary discs.Comment: Accepted to MNRAS. 18 pages, 14 figure
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