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MAS platforms as an enabler of enterprise mobilisation: The state of the art
One of the main application areas for multi-agent systems technology is enterprise mobilization, wherein the main business process actors are nomadic workers. An agent's autonomy, sociality and intelligence are highly prized features when it comes to supporting those mobile workers who are geographically isolated from the main knowledge source (i.e. the corporate Intranet) and are frequently moving from one location to another. Based on experience gained from two field trials of applications (built using for multi-agent systems technology and running on lightweight handheld devices) that support mobile business processes for telecommunications service provisioning and maintenance, this paper proposes desirable metrics for any multi-agent systems platform intended for enterprise mobilisation use. These metrics are then used to compare a number of existing multi-agent systems platforms, and based on the results, this paper identifies some areas for improvement
Wettability of Nanostructured Surfaces
There are many studies in literature concerning contact angle measurements on different materials/substrates. It is documented that textiles can be coated with multifunctional materials in form of thin films or nanoparticles to acquire characteristics that can improve the protection and comfort of the wearer. The capacity of oxide nanostructures to inhibit fungal development and neutralize bacteria is a direct consequence of their wetting behavior [1–6]. Moreover, the radical modification of wetting behavior of nanostructures from hydrophilic to hydrophobic when changing the pulsed laser deposition (PLD) ambient will be thoroughly discussed
Structure and hydration of membranes embedded with voltage-sensing domains.
Despite the growing number of atomic-resolution membrane protein structures, direct structural information about proteins in their native membrane environment is scarce. This problem is particularly relevant in the case of the highly charged S1-S4 voltage-sensing domains responsible for nerve impulses, where interactions with the lipid bilayer are critical for the function of voltage-activated ion channels. Here we use neutron diffraction, solid-state nuclear magnetic resonance (NMR) spectroscopy and molecular dynamics simulations to investigate the structure and hydration of bilayer membranes containing S1-S4 voltage-sensing domains. Our results show that voltage sensors adopt transmembrane orientations and cause a modest reshaping of the surrounding lipid bilayer, and that water molecules intimately interact with the protein within the membrane. These structural findings indicate that voltage sensors have evolved to interact with the lipid membrane while keeping energetic and structural perturbations to a minimum, and that water penetrates the membrane, to hydrate charged residues and shape the transmembrane electric field
The magnetic field environment of active region 12673 that produced the energetic particle events of September 2017
Forecasting solar energetic particles (SEPs), and identifying flare/CMEs from
active regions (ARs) that will produce SEP events in advance is extremely
challenging. We investigate the magnetic field environment of AR 12673,
including the AR's magnetic configuration, the surrounding field configuration
in the vicinity of the AR, the decay index profile, and the footpoints of
Earth-connected magnetic field, around the time of four eruptive events. Two of
the eruptive events are SEP-productive (2017 September 4 at 20:00~UT and
September 6 at 11:56~UT), while two are not (September 4 at 18:05~UT and
September 7 at 14:33~UT). We analysed a range of EUV and white-light
coronagraph observations along with potential field extrapolations and find
that the CMEs associated with the SEP-productive events either trigger null
point reconnection that redirects flare-accelerated particles from the flare
site to the Earth-connected field and/or have a significant expansion (and
shock formation) into the open Earth-connected field. The rate of change of the
decay index with height indicates that the region could produce a fast CME ( 1500~km~s), which it did during events two and three. The AR's
magnetic field environment, including sites of open magnetic field and null
points along with the magnetic field connectivity and propagation direction of
the CMEs play an important role in the escape and arrival of SEPs at Earth.
Other SEP-productive ARs should be investigated to determine whether their
magnetic field environment and CME propagation direction are significant in the
escape and arrival of SEPs at Earth.Comment: Accepted in ApJ, 18 pages, 8 Figures, 2 Table
Organic flexible heterostructures with Al:ZnO transparent conductor electrode for photovoltaic applications
Date du colloque : 10/2014International audienc
Evaluation Of Glueball Masses From Supergravity
In the framework of the conjectured duality relation between large gauge
theory and supergravity the spectra of masses in large gauge theory can be
determined by solving certain eigenvalue problems in supergravity. In this
paper we study the eigenmass problem given by Witten as a possible
approximation for masses in QCD without supersymmetry. We place a particular
emphasis on the treatment of the horizon and related boundary conditions. We
construct exact expressions for the analytic expansions of the wave functions
both at the horizon and at infinity and show that requiring smoothness at the
horizon and normalizability gives a well defined eigenvalue problem. We show
for example that there are no smooth solutions with vanishing derivative at the
horizon. The mass eigenvalues up to corresponding to smooth
normalizable wave functions are presented. We comment on the relation of our
work with the results found in a recent paper by Cs\'aki et al.,
hep-th/9806021, which addresses the same problem.Comment: 20 pages,Latex,3 figs,psfig.tex, added refs., minor change
Coded Aperture and Compton Imaging for the Development of Ac-based Radiopharmaceuticals
Targeted alpha-particle therapy (TAT) has great promise as a cancer
treatment. Arguably the most promising TAT radionuclide that has been proposed
is Ac. The development of Ac-based radiopharmaceuticals has
been hampered due to the lack of effective means to study the daughter
redistribution of these agents in small animals at the preclinical stage. The
ability to directly image the daughters, namely Fr and Bi, via
their gamma-ray emissions would be a boon for preclinical studies. That said,
conventional medical imaging modalities, including single photon emission
computed tomography (SPECT) based on pinhole collimation, cannot be employed
due to sensitivity limitations. As an alternative, we propose the use of both
coded aperture and Compton imaging with the former modality suited to the
218-keV gamma-ray emission of Fr and the latter suited to the 440-keV
gamma-ray emission of Bi. This work includes coded aperture images of
Fr and Compton images of Bi in tumor-bearing mice injected with
Ac-based radiopharmaceuticals. These results are the first
demonstration of visualizing and quantifying the Ac daughters in small
animals via coded aperture and Compton imaging and serve as a stepping stone
for future radiopharmaceutical studies
Evolution of Plasma Composition in an Eruptive Flux Rope
Magnetic flux ropes are bundles of twisted magnetic field enveloping a central axis. They harbor free magnetic energy and can be progenitors of coronal mass ejections (CMEs). However, identifying flux ropes on the Sun can be challenging. One of the key coronal observables that has been shown to indicate the presence of a flux rope is a peculiar bright coronal structure called a sigmoid. In this work, we show Hinode EUV Imaging Spectrometer observations of sigmoidal active region (AR) 10977. We analyze the coronal plasma composition in the AR and its evolution as a sigmoid (flux rope) forms and erupts as a CME. Plasma with photospheric composition was observed in coronal loops close to the main polarity inversion line during episodes of significant flux cancellation, suggestive of the injection of photospheric plasma into these loops driven by photospheric flux cancellation. Concurrently, the increasingly sheared core field contained plasma with coronal composition. As flux cancellation decreased and a sigmoid/flux rope formed, the plasma evolved to an intermediate composition in between photospheric and typical AR coronal compositions. Finally, the flux rope contained predominantly photospheric plasma during and after a failed eruption preceding the CME. Hence, plasma composition observations of AR 10977 strongly support models of flux rope formation by photospheric flux cancellation forcing magnetic reconnection first at the photospheric level then at the coronal level
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