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On being a mentor
This article explores issues relating to mentoring students, particularly ophthalmic nursing students. It highlights the importance of mentorship in learning in practice, which in turn is critical to students' education in a competency-based profession. It considers the factors essential in successful mentoring, including two-way feedback, and the importance of mentors understanding the nature of the psychological processes involved and how to assess students' learning and competencies. It also highlights the crucial gate-keeping role of mentors in ensuring that students are fit to practise, and the importance of nurse mentors themselves being fit to practise
Archaic mitochondrial DNA inserts in modern day nuclear genomes
Traces of interbreeding of Neanderthals and Denisovans with modern humans in the form of archaic DNA have been detected in the genomes of present-day human populations outside sub-Saharan Africa. Up to now, only nuclear archaic DNA has been detected in modern humans; we therefore attempted to identify archaic mitochondrial DNA (mtDNA) residing in modern human nuclear genomes as nuclear inserts of mitochondrial DNA (NUMTs)
Small Energy Scale for Mixed-Valent Uranium Materials
We investigate a two-channel Anderson impurity model with a magnetic
and a quadrupolar ground doublet, and a excited triplet. Using
the numerical renormalization group method, we find a crossover to a non-Fermi
liquid state below a temperature varying as the triplet-doublet
splitting to the 7/2 power. To within numerical accuracy, the non-linear
magnetic susceptibility and the contribution to the linear
susceptibility are given by universal one-parameter scaling functions. These
results may explain UBe as mixed valent with a small crossover scale
.Comment: 4 pages, 3 figures, REVTeX, to appear in Phys. Rev. Let
Discrete solitons in electromechanical resonators
We consider a parametrically driven Klein--Gordon system describing micro-
and nano-devices, with integrated electrical and mechanical functionality.
Using a multiscale expansion method we reduce the system to a discrete
nonlinear Schrodinger equation. Analytical and numerical calculations are
performed to determine the existence and stability of fundamental bright and
dark discrete solitons admitted by the Klein--Gordon system through the
discrete Schrodinger equation. We show that a parametric driving can not only
destabilize onsite bright solitons, but also stabilize intersite bright
discrete solitons and onsite and intersite dark solitons. Most importantly, we
show that there is a range of values of the driving coefficient for which dark
solitons are stable, for any value of the coupling constant, i.e. oscillatory
instabilities are totally suppressed. Stability windows of all the fundamental
solitons are presented and approximations to the onset of instability are
derived using perturbation theory, with accompanying numerical results.
Numerical integrations of the Klein--Gordon equation are performed, confirming
the relevance of our analysis
Aerodynamic performance of conventional and advanced design labyrinth seals with solid-smooth abradable, and honeycomb lands
Labyrinth air seal static and dynamic performance was evaluated using solid, abradable, and honeycomb lands with standard and advanced seal designs. The effects on leakage of land surface roughness, abradable land porosity, rub grooves in abradable lands, and honeycomb land cell size and depth were studied using a standard labyrinth seal. The effects of rotation on the optimum seal knife pitch were also investigated. Selected geometric and aerodynamic parameters for an advanced seal design were evaluated to derive an optimized performance configuration. The rotational energy requirements were also measured to determine the inherent friction and pumping energy absorbed by the various seal knife and land configurations tested in order to properly assess the net seal system performance level. Results indicate that: (1) seal leakage can be significantly affected with honeycomb or abradable lands; (2) rotational energy absorption does not vary significantly with the use of a solid-smooth, an abradable, or a honeycomb land; and (3) optimization of an advanced lab seal design produced a configuration that had leakage 25% below a conventional stepped seal
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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