304 research outputs found
Introducing a fifth pedagogy: Experience-based strategies for facilitating learning in natural environments
Educators have identified four categories of 'productive pedagogies' that are considered to lead to authentic student engagement and learning in the classroom. This study was designed to explore and extend these pedagogies in the context of learning in natural environments, in particular, through the programmes of Queensland environmental education centres. In-depth interview and observation data were collected from students, classroom teachers and centre teachers who had participated in 12 environmental education programmes across Queensland, in order to identify the strategies that are most effective in facilitating learning in the natural environment. A fifth productive pedagogy category, 'experience-based learning', is proposed. Experience-based learning is particularly important in addressing students' environmental attitudes and actions. The implications for the delivery of environmental education programmes both within and outside the classroom are discussed
Magnetic field effects on the density of states of orthorhombic superconductors
The quasiparticle density of states in a two-dimensional d-wave
superconductor depends on the orientation of the in-plane external magnetic
field H. This is because. in the region of the gap nodes, the Doppler shift due
to the circulating supercurrents around a vortex depend on the direction of H.
For a tetragonal system the induced pattern is four-fold symmetric and, at zero
energy, the density of states exhibits minima along the node directions. But
YBa_2C_3O_{6.95} is orthorhombic because of the chains and the pattern becomes
two-fold symmetric with the position of the minima occuring when H is oriented
along the Fermi velocity at a node on the Fermi surface. The effect of impurity
scattering in the Born and unitary limit is discussed.Comment: 24 pages, 11 Figure
Resonance fluorescence from a telecom-wavelength quantum dot
© 2016 Author(s).We report on resonance fluorescence from a single quantum dot emitting at telecom wavelengths. We perform high-resolution spectroscopy and observe the Mollow triplet in the Rabi regime - a hallmark of resonance fluorescence. The measured resonance-fluorescence spectra allow us to rule out pure dephasing as a significant decoherence mechanism in these quantum dots. Combined with numerical simulations, the experimental results provide robust characterisation of charge noise in the environment of the quantum dot. Resonant control of the quantum dot opens up new possibilities for the on-demand generation of indistinguishable single photons at telecom wavelengths as well as quantum optics experiments and direct manipulation of solid-state qubits in telecom-wavelength quantum dots
Detector Description and Performance for the First Coincidence Observations between LIGO and GEO
For 17 days in August and September 2002, the LIGO and GEO interferometer
gravitational wave detectors were operated in coincidence to produce their
first data for scientific analysis. Although the detectors were still far from
their design sensitivity levels, the data can be used to place better upper
limits on the flux of gravitational waves incident on the earth than previous
direct measurements. This paper describes the instruments and the data in some
detail, as a companion to analysis papers based on the first data.Comment: 41 pages, 9 figures 17 Sept 03: author list amended, minor editorial
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Prevention and control of multi-drug-resistant Gram-negative bacteria: recommendations from a Joint Working Party
Multi-drug-resistant (MDR) Gram-negative bacterial infections have become prevalent in some European countries. Moreover, increased use of broad-spectrum antimicrobial agents selects organisms with resistance and, by increasing their numbers, increases their chance of spread. This report describes measures that are clinically effective for preventing transmission when used by healthcare workers in acute and primary healthcare premises. Methods for systematic review 1946–2014 were in accordance with SIGN 501 and the Cochrane Collaboration;2 critical appraisal was applied using AGREEII.3 Accepted guidelines were used as part of the evidence base and to support expert consensus. Questions for review were derived from the Working Party Group, which included patient representatives in accordance with the Patient Intervention Comparison Outcome (PICO) process. Recommendations are made in the following areas: screening, diagnosis and infection control precautions including hand hygiene, single-room accommodation, and environmental screening and cleaning. Recommendations for specific organisms are given where there are species differences. Antibiotic stewardship is covered in a separate publication
Avaliação da eficácia do fipronil em Rhipicephalus (Boophilus) microplus em tratamentos consecutivos
A Theory for the High-T_c Cuprates: Anomalous Normal-State and Spectroscopic Properties, Phase Diagram, and Pairing
A theory of highly correlated layered superconducting materials isapplied for
the cuprates. Differently from an independent-electron approximation, their
low-energy excitations are approached in terms of auxiliary particles
representing combinations of atomic-like electron configurations, where the
introduction of a Lagrange Bose field enables treating them as bosons or
fermions. The energy spectrum of this field accounts for the tendency of
hole-doped cuprates to form stripe-like inhomogeneities. Consequently, it
induces a different analytical behavior for auxiliary particles corresponding
to "antinodal" and "nodal" electrons, enabling the existence of different
pairing temperatures at T^* and T_c. This theory correctly describes the
observed phase diagram of the cuprates, including the non-Fermi-liquid to FL
crossover in the normal state, the existence of Fermi arcs below T^* and of a
"marginal-FL" critical behavior above it. The qualitative anomalous behavior of
numerous physical quantities is accounted for, including kink- and
waterfall-like spectral features, the drop in the scattering rates below T^*
and more radically below T_c, and an effective increase in the density of
carriers with T and \omega, reflected in transport, optical and other
properties. Also is explained the correspondence between T_c, the
resonance-mode energy, and the "nodal gap".Comment: 28 pages, 7 figure
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