23,151 research outputs found
Sustainability of social-emotional learning and related programs : lessons from a field study
Social-emotional learning, character education, and related programs are being
implemented in schools with increasing frequency and research supports their short-term
effectiveness. However, there has been no empirical work to date that identifies the
factors important for the long-term sustainability of programs established as excellent
models of implementation. Using a series of case studies of evidence-based socialemotional learning programs implemented successfully for at least five years, this study articulates principles that characterize programs that were found to be well-sustained over time. These principles have implications for practice and serve as starting points for future research.peer-reviewe
Semi-optimal Practicable Algorithmic Cooling
Algorithmic Cooling (AC) of spins applies entropy manipulation algorithms in
open spin-systems in order to cool spins far beyond Shannon's entropy bound. AC
of nuclear spins was demonstrated experimentally, and may contribute to nuclear
magnetic resonance (NMR) spectroscopy. Several cooling algorithms were
suggested in recent years, including practicable algorithmic cooling (PAC) and
exhaustive AC. Practicable algorithms have simple implementations, yet their
level of cooling is far from optimal; Exhaustive algorithms, on the other hand,
cool much better, and some even reach (asymptotically) an optimal level of
cooling, but they are not practicable. We introduce here semi-optimal
practicable AC (SOPAC), wherein few cycles (typically 2-6) are performed at
each recursive level. Two classes of SOPAC algorithms are proposed and
analyzed. Both attain cooling levels significantly better than PAC, and are
much more efficient than the exhaustive algorithms. The new algorithms are
shown to bridge the gap between PAC and exhaustive AC. In addition, we
calculated the number of spins required by SOPAC in order to purify qubits for
quantum computation. As few as 12 and 7 spins are required (in an ideal
scenario) to yield a mildly pure spin (60% polarized) from initial
polarizations of 1% and 10%, respectively. In the latter case, about five more
spins are sufficient to produce a highly pure spin (99.99% polarized), which
could be relevant for fault-tolerant quantum computing.Comment: 13 pages, 5 figure
S-matrix bootstrap for resonances
We study the -matrix element of a generic, gapped and
Lorentz invariant QFT in space time dimensions. We derive an analytical
bound on the coupling of the asymptotic states to unstable particles (a.k.a.
resonances) and its physical implications. This is achieved by exploiting the
connection between the S-matrix phase-shift and the roots of the S-matrix in
the physical sheet. We also develop a numerical framework to recover the
analytical bound as a solution to a numerical optimization problem. This later
approach can be generalized to spacetime dimensions.Comment: Minor typos corrected, matches published versio
One-loop non-renormalization results in EFTs
In Effective Field Theories (EFTs) with higher-dimensional operators many
anomalous dimensions vanish at the one-loop level for no apparent reason. With
the use of supersymmetry, and a classification of the operators according to
their embedding in super-operators, we are able to show why many of these
anomalous dimensions are zero. The key observation is that one-loop
contributions from superpartners trivially vanish in many cases under
consideration, making supersymmetry a powerful tool even for non-supersymmetric
models. We show this in detail in a simple U(1) model with a scalar and
fermions, and explain how to extend this to SM EFTs and the QCD Chiral
Langrangian. This provides an understanding of why most "current-current"
operators do not renormalize "loop" operators at the one-loop level, and allows
to find the few exceptions to this ubiquitous rule.Comment: Corrections made in Sec. 3.2 and Fig.
WTO safeguards and trade liberalization: lessons from the Argentine footwear case
The footwear case provides an example of the complexities of World Trade Organization (WTO) rules on the use of safeguards, and of the interaction of multilateral and regional processes of liberalization. As a result both of Argentina's unilateral liberalization and the removal of barriers within Mercosur, imports of footwear increased rapidly. As Mercosur provides no intra-regional safeguard mechanism, the government of Argentina responded by applying import relief and WTO safeguards against third countries. The WTO Dispute Settlement Body addressed these measures and as a consequence, Argentina dismantled most of them, leading to four main conclusions: The jurisprudence of the WTO's Appellate Body has created serious uncertainty as to when a country can use safeguards. This does not contribute to the political balance that has to be maintained when developing countries implement trade liberalization programs. In fact, it detracts from this crucial goal. It is an error to negotiate ambiguous multilateral agreements on the expectation that the WTO Dispute Settlement mechanism will clarify them. An overvalued currency heightened the industry's problems. In the case of footwear, the decline in imports following the recent devaluation was more important than that following the implementation of earlier relief measures. The political economy of liberalization also indicates the need for regional agreements to include adequate transition mechanisms that will facilitate adjustment to free trade and to maintain support for it.Trade Policy,Rules of Origin,TF054105-DONOR FUNDED OPERATION ADMINISTRATION FEE INCOME AND EXPENSE ACCOUNT,Environmental Economics&Policies,Economic Theory&Research
Educational Performance and Spatial Convergence in Peru
While an enormous and growing literature exists on the topic of regional income convergence, other aspects of socioeconomic well-being and development have attracted much less attention. Social indicators are a valuable complement to economic indicators when analyzing spatial patterns in a given geographic region, and can often yield a more comprehensive view about regional socioeconomic behavior. In poorer nations dominated by many low income areas that exhibit similar economic performance, social indicators may reveal further insight into the differences among regions. This paper explores the issue of educational convergence in Peru over the period 1993 to 2005. Using both exploratory spatial data analysis and spatial econometrics, the study is conducted at province level in order to uncover potential spatial patterns that help explain variation in educational performance over time, among regions, and across different terrain.
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