2,597 research outputs found
Developing sexual competence? Exploring strategies for the provision of effective sexualities and relationships education
School-based sexualities and relationships education (SRE) offers one of the most promising means of improving young people's sexual health through developing 'sexual competence'. In the absence of evidence on whether the term holds the same meanings for young people and adults (e.g. teachers, researchers, policy-makers), the paper explores 'adult' notions of sexual competence as construed in research data and alluded to in UK Government guidance on SRE, then draws on empirical research with young people on factors that affect the contexts, motivations and outcomes of sexual encounters, and therefore have implications for sexual competence. These data from young people also challenge more traditional approaches to sexualities education in highlighting disjunctions between the content of school-based input and their reported sexual experience. The paper concludes by considering the implications of these insights for developing a shared notion of what SRE is trying to achieve and suggestions for recognition in the content and approaches to SRE.</p
Quasi-Moessbauer effect in two dimensions
Expressions for the absorption spectrum of a nucleus in a three- and a
two-dimensional crystal respectively are obtained analytically at zero and at
finite temperature respectively. It is found that for finite temperature in two
dimensions the Moessbauer effect vanishes but is replaced by what we call a
Quasi-Moessbauer effect. Possibilities to identify two-dimensional elastic
behavior are discussed.Comment: 18 pages, 5 figures, notation simplifie
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Exposing the myth of the 1:5:200 ratio relating initial cost, maintenance and staffing costs of office buildings
In an attempt to focus clients' minds on the importance of considering the construction and maintenance costs of a commercial office building (both as a factor in staff productivity and as a fraction of lifetime staff costs) there is an often-quoted ratio of costs of 1:5:200, where for every one pound spent on construction cost, five are spent on maintenance and building operating costs and 200 on staffing and business operating costs. This seems to stem from a paper published by the Royal Academy of Engineering, in which no data is given and no derivation or defence of the ratio appears. The accompanying belief that higher quality design and construction increases staff productivity, and simultaneously reduces maintenance costs, how ever laudable, appears unsupported by research, and carries all the hallmarks of an "urban myth". In tracking down data about real buildings, a more realistic ratio appears to depend on a huge variety of variables, as well as the definition of the number of "lifetime" years. The ill-defined origins of the original ratio (1:5:200) describing these variables have made replication impossible. However, by using published sources of data, we have found that for three office buildings, a more realistic ratio is 1:0.4:12. As there is nothing in the public domain about what comprised the original research that gave rise to 1:5:200, it is not possible to make a true comparison between these new calculations and the originals. Clients and construction professionals stand to be misled because the popularity and widespread use of the wrong ratio appears to be mis-informing important investment and policy decisions
Crystal Distortion and the Two-Channel Kondo Effect
We study a simple model of the two-channel Kondo effect in a distorted
crystal. This model is then used to investigate the interplay of the Kondo and
Jahn-Teller effects, and also the Kondo effect in an impure crystal. We find
that the Jahn-Teller interaction modifies the characteristic energy scale of
the system below which non-Fermi-liquid properties of the model become
apparent. The modified energy scale tends to zero as the limit of a purely
static Jahn-Teller effect is approached. We find also that the non-Fermi-liquid
properties of the quadrupolar Kondo effect are not stable against crystal
distortion caused by impurities.Comment: 11 page
Crossover between Fermi Liquid and non-Fermi Liquid in Orbitally Degenerate Kondo Systems
Entanglement of spin and orbital Kondo effect is investigated on the basis of
a Kondo-type exchange model with twofold orbital degeneracy. By using Wilson's
numerical renormalization-group method, we examine dynamical and thermal
properties respecting the difference in time-reversal property of multipole
operators. In the presence of particle-hole symmetry, the model has a new
non-Fermi-liquid fixed point with a fractional entropy. The spectral intensity
of the quadrupole susceptibility diverges in the zero-frequency limit, while
the dipole susceptibility shows a Fermi-liquid-like behavior. This is
understood by mapping to the two-channel Kondo model, in which the dipole
moment is mapped onto the operators with the scaling dimension ,
while the quadrupole moment onto the operators with another scaling dimension
. Even for a fairly particle-hole asymmetric case with the
Fermi-liquid ground state, the non-Fermi-liquid behavior has significant
influences in electric and thermal properties.Comment: 7 pages, 9 figures, to appear in J. Phys Soc. Jpn. Vol. 68 No. 12,
title changed and some corrections mad
The CSIRO Mk3L climate system model version 1.0 – Part 1: Description and evaluation
The CSIRO Mk3L climate system model is a coupled general circulation model, designed primarily for millennial-scale climate simulations and palaeoclimate research. Mk3L includes components which describe the atmosphere, ocean, sea ice and land surface, and combines computational efficiency with a stable and realistic control climatology. This paper describes the model physics and software, analyses the control climatology, and evaluates the ability of the model to simulate the modern climate. <br><br> Mk3L incorporates a spectral atmospheric general circulation model, a <i>z</i>-coordinate ocean general circulation model, a dynamic-thermodynamic sea ice model and a land surface scheme with static vegetation. The source code is highly portable, and has no dependence upon proprietary software. The model distribution is freely available to the research community. A 1000-yr climate simulation can be completed in around one-and-a-half months on a typical desktop computer, with greater throughput being possible on high-performance computing facilities. <br><br> Mk3L produces realistic simulations of the larger-scale features of the modern climate, although with some biases on the regional scale. The model also produces reasonable representations of the leading modes of internal climate variability in both the tropics and extratropics. The control state of the model exhibits a high degree of stability, with only a weak cooling trend on millennial timescales. Ongoing development work aims to improve the model climatology and transform Mk3L into a comprehensive earth system model
Developing the Saegusa-Ito cyclisation for the synthesis of difluorinated cyclohexenones
Palladium(II)-catalysed cycloalkenylation (Saegusa-Ito cyclisation) has been used for the first time to transform difluorinated silylenol ethers to difluorinated cycloalkenones under mild conditions. The silylenol ether precursors were prepared in two high-yielding steps from trifluoroethanol, and cyclised in moderate to good yields. A combination of air and copper(I) chloride in acetonitrile achieved the turnover of the initial palladium(II) salt, while the provision of an oxygen atmosphere ensured more rapid reaction. Annulations required a minimum level of substitution on the chain, but failed when the alkene was substituted. Annelations allowed a range of n,6-bicyclic systems to be prepared and afforded three products in which heterocycles were fused to the new cyclohexenone. The least substituted system explored underwent cyclisation followed by terminal oxidation to a cyclic enal, which corresponded to a Wacker product of unusual regiochemistry
Singlet Magnetism in Heavy Fermions
We consider singlet magnetism for the uranium ions in UPt and
URuSi assuming that time-reversal symmetry is broken for the {\em
coherent state of intermediate valence}. The relative weight of the two
involved configurations should be different for UPt and URuSi. If
in UPt the configuration on the U-ion prevails in the coherent state
below the magnetic transition, the magnetic moment would vanish for the
particular choice of the {\em ionic} wave function. In case of URuSi,
the phase transition is non-magnetic in the first approximation -- the magnetic
moment arises from a small admixture of a half-integer spin configuration.Comment: 12 pages, RevTex, no figures; Phys. Rev. Lett., to appea
Scaling analysis of a model Hamiltonian for Ce impurity in a cubic metal
We introduce various exchange interactions in a model Hamiltonian for
Ce ions in cubic symmetry with three configurations (,,).
With the impurity pseudo spin , our Hamiltonian includes: (i)
One-channel Anderson model; (ii) Two-channel Anderson
model; (iii) An unforseen one-channel Anderson model with a
non-trivial fixed point; (iv) Mixing exchange interaction between the
and the conduction electron partial wave states; (v)
Multiple conduction electron partial wave states. Using the third-order scaling
(perturbative renormalization group) analysis, we study stability of various
fixed points relevant to various exchange interactions for Ce ions in
cubic symmetry.Comment: 68 pages. 4 figures are available upon request from
[email protected] (revised
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