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Overcoming restrictive technologies in police call centres: A human agency perspective
Call centres in the police force are restrictive information systems which tend to present call
operators with constraints that they need to overcome using their experience in order to offer
better services to the public. This paper is looking at how elements of human agency come in
to play and help users’ enactment against restrictive technologies. Information systems
research on human agency has been mainly focused on the examination of whether agency
lies within human or machines or both while in this paper we take a different approach and
we clearly describe how human agency is enacted in practice. We use empirical data from
contact centres and operational rooms of five UK police forces. After extensive observations
we present how police call handlers manipulate digital information efficiently through human
agency. The theoretical framework is based on the three elements of agency theory (iteration,
projectivity and practical evaluation) The research findings assert that call handlers
overcome the restrictions of the system by forming human-digital networks and using mental
structures from their past experience in order to cope with the task at hand. The paper
concludes by drawing implications for theory and practice and suggests future research
directions
The Human Development Index Adjusted for Efficient Resource Utilization
human development index, data envelopment analysis, efficiency, congestion and scale economics
An introductory note on Quasicrystals
This paper presents a brief introduction of the research on a new class of materials called quasicrystals. Starting from history of its development, paper discusses about its growth mechanism and its applications. Contents of the paper are based on various sources available and no originality of the article is claimed by the author
Sarcoma immunotherapy.
Much of our knowledge regarding cancer immunotherapy has been derived from sarcoma models. However, translation of preclinical findings to bedside success has been limited in this disease, though several intriguing clinical studies hint at the potential efficacy of this treatment modality. The rarity and heterogeneity of tumors of mesenchymal origin continues to be a challenge from a therapeutic standpoint. Nonetheless, sarcomas remain attractive targets for immunotherapy, as they can be characterized by specific epitopes, either from their mesenchymal origins or specific alterations in gene products. To date, standard vaccine trials have proven disappointing, likely due to mechanisms by which tumors equilibrate with and ultimately escape immune surveillance. More sophisticated approaches will likely require multimodal techniques, both by enhancing immunity, but also geared towards overcoming innate mechanisms of immunosuppression that favor tumorigenesis
Turbulence and Mixing in the Intracluster Medium
The intracluster medium (ICM) is stably stratified in the hydrodynamic sense
with the entropy increasing outwards. However, thermal conduction along
magnetic field lines fundamentally changes the stability of the ICM, leading to
the "heat-flux buoyancy instability" when and the "magnetothermal
instability" when . The ICM is thus buoyantly unstable regardless of
the signs of and . On the other hand, these
temperature-gradient-driven instabilities saturate by reorienting the magnetic
field (perpendicular to when and parallel to when ), without generating sustained convection. We show that
after an anisotropically conducting plasma reaches this nonlinearly stable
magnetic configuration, it experiences a buoyant restoring force that resists
further distortions of the magnetic field. This restoring force is analogous to
the buoyant restoring force experienced by a stably stratified adiabatic
plasma. We argue that in order for a driving mechanism (e.g, galaxy motions or
cosmic-ray buoyancy) to overcome this restoring force and generate turbulence
in the ICM, the strength of the driving must exceed a threshold, corresponding
to turbulent velocities . For weaker driving, the ICM
remains in its nonlinearly stable magnetic configuration, and turbulent mixing
is effectively absent. We discuss the implications of these findings for the
turbulent diffusion of metals and heat in the ICM.Comment: 8 pages, 2 figs., submitted to the conference proceedings of "The
Monster's Fiery Breath;" a follow up of arXiv:0901.4786 focusing on the
general mixing properties of the IC
Unified equation of state for neutron stars on a microscopic basis
We derive a new equation of state (EoS) for neutron stars (NS) from the outer
crust to the core based on modern microscopic Brueckner-Hartree-Fock (BHF)
calculations using the Argonne potential plus three-body forces
computed with the Urbana model. To deal with the inhomogeneous structures of
matter in the NS crust, we use the recent Barcelona-Catania-Paris-Madrid (BCPM)
nuclear energy density functional that is directly based on the same
microscopic BHF calculations, and which is able to reproduce the ground-state
properties of nuclei along the periodic table. The EoS of the outer crust
requires the masses of neutron-rich nuclei, which are obtained through
Hartree-Fock-Bogoliubov calculations with the BCPM functional when they are
unknown experimentally. To compute the inner crust, Thomas-Fermi calculations
in Wigner-Seitz cells are performed with the same functional. Existence of
nuclear pasta is predicted in a range of average baryon densities between
0.067 fm and 0.0825 fm, where the transition to
the core takes place. The NS core is computed from the nuclear EoS of the BHF
calculation assuming non-exotic constituents (core of matter). In each
region of the star, we discuss the comparison of the new EoS with previous
EoSes for the complete NS structure, in particular, with the Lattimer-Swesty
EoS and with the Shen et al. EoS widely used in astrophysical calculations. The
new microscopically derived EoS fulfills at the same time a NS maximum mass of
2~ with a radius of 10 km, and a 1.5~ NS with a radius of
11.7 km.Comment: 23 pages, 17 figures, revised version accepted for publication in
Astronomy & Astrophysic
The nuclear shell effects near the r-process path in the relativistic Hartree-Bogoliubov theory
We have investigated the evolution of the shell structure of nuclei in going
from the r-process path to the neutron drip line within the framework of the
Relativistic Hartree-Bogoliubov (RHB) theory. By introducing the quartic
self-coupling of meson in the RHB theory in addition to the non-linear
scalar coupling of meson, we reproduce the available data on the shell
effects about the waiting-point nucleus Zn. With this approach, it is
shown that the shell effects at N=82 in the inaccessible region of the
r-process path become milder as compared to the Lagrangian with the scalar
self-coupling only. However, the shell effects remain stronger as compared to
the quenching exhibited by the HFB+SkP approach. It is also shown that in
reaching out to the extreme point at the neutron drip line, a terminal
situation arises where the shell structure at the magic number is washed out
significantly.Comment: 18 pages (revtex), 8 ps figures, to appear in Phys. Rev.
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