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Editorial for special issue on education and humour: Education and humour as tools for social awareness and critical consciousness in contemporary classrooms
It is not new to consider the instructive power of humour. Both Plato and Aristotle, through their superiority theories, saw the benefit of wit as a social corrective, although they remained suspicious of the uneducated laughter of the masses (Plato in Morreall 1987; Aristotle in Morreall 1987). This approach has informed traditions of satire and resistance humour in a myriad of contexts. Stott summarises the raison d'ĂȘtre of satire through its aim âto denounce folly and vice and urge ethical and political reform through the subjection of ideas to humorous analysisâ (Stott 2005: 109). The political potential of humour is easily recognised as a rhetorical and communicative device, yet it seems odd that little stock has been placed academically or culturally in the idea of humour as an educative tool in other social and cultural contexts and, more specifically, in the classroom
The Regulation of Residential Tenancy Markets in Post-War Western Europe: An Economic Analysis
This paper provides an economic analysis of the post-war regulation of European tenancy markets. Two representative types of market regulation are analyzed: the introduction of compulsory duration clauses in tenancy contracts (as a means of protecting the tenant against eviction); and rent control policies. First, the study describes and analyzes the recent history of such regulations in Spain, Italy, Finland and the UK, in order to draw some general conclusions about the evolution of European institutions in recent decades. Their effects are then explored by adapting a theoretical model of tenancy markets. The results show that both rent control and compulsory duration clauses potentially entail negative effects for European tenancy markets as they may drive some participants out of the market. These effects are consistent with the trends observed during the latter half of the 20th century in several European countries.Rent control, Tenancy contracts, Compulsory terms
On-chip quantum tomography of mechanical nano-scale oscillators with guided Rydberg atoms
Nano-mechanical oscillators as well as Rydberg-atomic waveguides hosted on
micro-fabricated chip surfaces hold promise to become pillars of future quantum
technologies. In a hybrid platform with both, we show that beams of Rydberg
atoms in waveguides can quantum-coherently interrogate and manipulate
nanomechanical elements, allowing full quantum state tomography. Central to the
tomography are quantum non-demolition measurements using the Rydberg atoms as
probes. Quantum coherent displacement of the oscillator is also made possible,
by driving the atoms with external fields while they interact with the
oscillator. We numerically demonstrate the feasibility of this fully integrated
on-chip control and read-out suite for quantum nano-mechanics, taking into
account noise and error sources.Comment: 11 pages, 5 figures, 1 tabl
Multitarget tracking via restless bandit marginal productivity indices and Kalman Filter in discrete time
This paper designs, evaluates, and tests a tractable priority-index policy for scheduling target updates in a discrete-time multitarget tracking model, which aims to be close to optimal relative to a discounted or average performance objective accounting for tracking-error variance and measurement costs. The policy is to be used by a sensor system composed of M phased-array radars coordinated to track the positions of N targets moving according to independent scalar Gauss-Markov linear dynamics, which therefore allows for the use of the Kalman Filter for track estimation. The paper exploits the natural problem formulation as a multiarmed restless bandit problem (MARBP) with real-state projects subject to deterministic dynamics by deploying Whittle's (1988) index policy for the MARBP. The challenging issues of indexability (existence of the index) and index evaluation are resolved by applying a method recently introduced by the first author for the analysis of real-state restless bandits. Computational results are reported demonstrating the tractability of index evaluation, the substantial performance gains that the Whittle's marginal productivity (MP) index policy achieves against myopic policies advocated in previous work and the resulting index policies suboptimality gaps. Further, a preliminary small scale computational study shows that the (MP) index policy exhibits a nearly optimal behavior as the number of distinct objective targets grows with the number of radars per target constant.Multitarget tracking, Sensor management, Phased array radar, Radar scheduling, Scaled track-error variance (STEV), Kalman Filter, Index policy, Marginal productivity (MP) index, Real-state multiarmed restless bandit problems (MARBP)
Covariant Lagrangian Formulation of Chern-Simons and BF Theories
We investigate the covariant formulation of Chern-Simons theories in a
general odd dimension which can be obtained by introducing a vacuum connection
field as a reference. Field equations, Noether currents and superpotentials are
computed so that results are easily compared with the well-known results in
dimension 3. Finally we use this covariant formulation of Chern-Simons theories
to investigate their relation with topological BF theories.Comment: 23 pages, refs. adde
Limits of sensing temporal concentration changes by single cells
Berg and Purcell [Biophys. J. 20, 193 (1977)] calculated how the accuracy of
concentration sensing by single-celled organisms is limited by noise from the
small number of counted molecules. Here we generalize their results to the
sensing of concentration ramps, which is often the biologically relevant
situation (e.g. during bacterial chemotaxis). We calculate lower bounds on the
uncertainty of ramp sensing by three measurement devices: a single receptor, an
absorbing sphere, and a monitoring sphere. We contrast two strategies, simple
linear regression of the input signal versus maximum likelihood estimation, and
show that the latter can be twice as accurate as the former. Finally, we
consider biological implementations of these two strategies, and identify
possible signatures that maximum likelihood estimation is implemented by real
biological systems.Comment: 11 pages, 2 figure
Energy dependence of the quark masses and mixings
The one loop Renormalization Group Equations for the Yukawa couplings of
quarks are solved. From the solution we find the explicit energy dependence on
of the evolution of the {\em down} quark masses from
the grand unification scale down to the top quark mass . These results
together with the earlier published evolution of the {\em up} quark masses
completes the pattern of the evolution of the quark masses. We also find the
energy dependence of the absolute values of the Cabibbo-Kobayashi-Maskawa (CKM)
matrix . The interesting property of the evolution of the CKM matrix
and the ratios of the quark masses: and is that
they all depend on through only one function of energy .Comment: Talk presented at the IX Mexican School on Particles and Fields,
August 9-19, Metepec, Pue., Mexico. To be published in the AIP Conference
Proceedings. 5 pages and 1 eps figure included in the tex
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