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The development of self-injury as a multi-functional behaviour
In order to advance our understanding of self-injury this longitudinal study investigated the experiences of 25 adults who had used or were using self-injury. This was achieved by obtaining verbal narrative accounts of their experiences of using self-injury from its onset during childhood or early adolescence, throughout adolescence and into adulthood. These verbatim accounts formed a corpus of data which was analysed using a grounded theory method. This process established seven robust categories associated with the use of self-injury consisting of behavioural, cognitive, emotional, social, occupational, communication and physiological experiences. By thoroughly examining these categories the development of self-injury as a versatile multi-functional behaviour emerged which was governed by the individuals‟ needs. Evidence for these multiple uses stemmed from the similarities that developed in the individuals‟ use of self-injury over time. Highlighting these multiple functions it was established that improved social, communication and occupational conditions were crucial aspects in the participants‟ reduction in using self-injury. The contribution this research has made towards developing our understanding of self-injury was addressed, particularly in relation to its use by the non-clinically defined members of the general public who took part, and in the context of advancing relevant nursing research and practice. Several critical aspects of the methodology were identified, in particular the restrictive generalisation of the findings to others who self-injure, and the use of retrospective accounts were discussed and directives were outlined to improve these aspects in future research. Proposals were made for further research to clarify and investigate the multiple functions of self-injury and to increase our understanding of the continuing use of covert self-injury during adulthood. Additionally, the relevance of the findings to nursing practice, principally in relation to adequately assessing the use of self-injury was discussed
Comparison of the full potential and Euler formulations for computing transonic airfoil flows
A quantitative comparison between the Euler and full potential formulations with respect to speed and accuracy is presented. The robustness of the codes used is tested by a number of transonic airfoil cases. The computed results are from four transonic airfoil computer codes. The full potential codes use fully implicit iteration algorithms. The first Euler code uses a fully implicit ADI iteration scheme. The second Euler code uses an explicit Runge Kutta time stepping algorithm which is enhanced by a multigrid convergence acceleration scheme. Quantitative comparisons are made using various plots of lift coefficient versus the average mesh spacing along the airfoil. Besides yielding an asymptotic limit to the lift coefficient, these results also demonstrate the truncation error behavior of the various codes. Quantitative conclusions regarding the full potential and Euler formulations with respect to accuracy, speed, and robustness can be presented
Electrical and magnetic properties of the complete solid solution series between SrRuO3 and LaRhO3: Filling t2g versus tilting
A complete solid solution series between the t2g^4 perovskite ferromagnet
SrRuO3 and the diamagnetic t2g^6 perovskite LaRhO3 has been prepared. The
evolution with composition x in (SrRuO3)(1-x)(LaRhO3)(x) of the crystal
structure and electrical and magnetic properties has been studied and is
reported here. As x increases, the octahedral tilt angle gradually increases,
along with the pseudocubic lattice parameter and unit cell volume. Electrical
resistivity measurements reveal a compositionally driven metal to insulator
transition between x = 0.1 and 0.2. Ferromagnetic ordering gives over to glassy
magnetism for x > 0.3 and no magnetic ordering is found above 2 K for x > 0.5.
M_sat and Theta_CW decrease with increasing x and remain constant after x =
0.5. The magnetism appears poised between localized and itinerant behavior, and
becomes more localized with increasing x as evidenced by the evolution of the
Rhodes-Wohlfarth ratio. mu_eff per Ru is equal to the quenched spin-only S
value across the entire solid solution. Comparisons with Sr(1-x)Ca(x)RuO3
reinforce the important role of structural distortions in determining magnetic
ground state. It is suggested that electrical transport and magnetic properties
are not strongly coupled in this system
Low-background temperature sensors fabricated on parylene substrates
Temperature sensors fabricated from ultra-low radioactivity materials have
been developed for low-background experiments searching for neutrinoless
double-beta decay and the interactions of WIMP dark matter. The sensors consist
of electrical traces photolithographically-patterned onto substrates of
vapor-deposited parylene. They are demonstrated to function as expected, to do
so reliably and robustly, and to be highly radio-pure. This work is a
proof-of-concept study of a technology that can be applied to broad class of
electronic circuits used in low-background experiments
Theoretical studies of Si and GaAs surfaces and initial steps in the oxidation
Using ab initio quantum chemical methods (generalized valence bond), we examine (i) the electronic states of Si (111) and GaAs (110) surface, (ii) the relaxation of the Si (111) surface, (iii) the reconstruction of the GaAs surface, (iv) the initial steps in the chemisorption of O_2 on Si (111), and (v) the bonding of O atom to Ga and As centers
Tunnel switch diode based on AlSb/GaSb heterojunctions
We report on tunnel switch diodes based on AlSb barriers and GaSb p–n junctions grown by molecular beam epitaxy. These were the devices with thyristor like switching in the GaSb/AlSb system. The characteristic "S" shaped current–voltage curve was found to occur for structures with AlSb barriers less than 300 Å thick. The switching voltage and current density exhibited less sensitivity to barrier and epilayer thickness than was predicted by the punch-through model. The results were correlated with drift diffusion simulations which have been modified to account for the presence of a tunneling contact
Phase diagram of a generalized ABC model on the interval
We study the equilibrium phase diagram of a generalized ABC model on an
interval of the one-dimensional lattice: each site is occupied by a
particle of type \a=A,B,C, with the average density of each particle species
N_\a/N=r_\a fixed. These particles interact via a mean field
non-reflection-symmetric pair interaction. The interaction need not be
invariant under cyclic permutation of the particle species as in the standard
ABC model studied earlier. We prove in some cases and conjecture in others that
the scaled infinite system N\rw\infty, i/N\rw x\in[0,1] has a unique
density profile \p_\a(x) except for some special values of the r_\a for
which the system undergoes a second order phase transition from a uniform to a
nonuniform periodic profile at a critical temperature .Comment: 25 pages, 6 figure
Searching for Star Formation Beyond Reionization
The goal of searching back in cosmic time to find star formation during the
epoch of reionization will soon be within reach. We assess the detectability of
high-redshift galaxies by combining cosmological hydrodynamic simulations of
galaxy formation, stellar evolution models appropriate for the first
generations of stars, and estimates of the efficiency for Lyman alpha to escape
from forming galaxies into the intergalactic medium. Our simulated observations
show that Lyman alpha emission at z ~ 8 may be observable in the near-infrared
with 8-meter class telescopes and present-day technology. Not only is the
detection of early star-forming objects vital to understanding the underlying
cause of the reionization of the universe, but the timely discovery of a z > 7
star-forming population -- or even an interesting upper limit on the emergent
flux from these objects -- will have implications for the design of the next
generation of ground- and space-based facilities.Comment: 4 pages, submitted to ApJ Letter
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