9,848 research outputs found
Blood ties : the labyrinth of family membership in long term adoption reunion : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Social Anthropology at Massey University
This thesis reports original research conducted with twenty adoptees, adopted under closed-stranger protocols, who have been experiencing regular post-reunion contact with their birth families for more than ten years. It examines the themes of the mothering role, family obligation and family membership to uncover how adoptees navigate their family membership within and between two families (adoptive and birth family). This study presents the thoughts, feelings and observations of the participants in their own words to convey a deeper understanding of their experiences. Drawing upon in-depth interviews, this study has sought to expand on earlier research focusing on the search and reunion and immediate post-reunion stages to examine the long-term experiences of adoptees in post-reunion. The principal finding is that reunited relationships have no predictable pathways and are approached with varying levels of ambivalence and emotional strain, and that there is no fixed pattern of family arrangements and relational boundaries. While closed-stranger adoptions and the subsequent reunions may eventually cease, this research may assist in understanding the issues surrounding the reunion between gamete (egg) and sperm donor's and their offspring in the future. KEYWORDS: Adoption Post-reunion, Adoptee, Birth Family, Family Membership, Family Relationships, Closed Adoption Reunion
Power-free values of polynomials on symmetric varieties
Given a symmetric variety Y defined over the rationals and a non-zero
polynomial with integer coefficients, we use techniques from homogeneous
dynamics to establish conditions under which the polynomial can be made r-free
for a Zariski dense set of integral points on Y. We also establish an
asymptotic counting formula for this set. In the special case that Y is a
quadric hypersurface, we give explicit bounds on the size of r by combining the
argument with a uniform upper bound for the density of integral points on
general affine quadrics.Comment: 47 pages; accepted versio
Modeling the Rise of Fibril Magnetic Fields in Fully Convective Stars
Many fully convective stars exhibit a wide variety of surface magnetism,
including starspots and chromospheric activity. The manner by which bundles of
magnetic field traverse portions of the convection zone to emerge at the
stellar surface is not especially well understood. In the Solar context, some
insight into this process has been gleaned by regarding the magnetism as
consisting partly of idealized thin flux tubes (TFT). Here, we present the
results of a large set of TFT simulations in a rotating spherical domain of
convective flows representative of a 0.3 solar-mass, main-sequence star. This
is the first study to investigate how individual flux tubes in such a star
might rise under the combined influence of buoyancy, convection, and
differential rotation. A time-dependent hydrodynamic convective flow field,
taken from separate 3D simulations calculated with the anelastic equations,
impacts the flux tube as it rises. Convective motions modulate the shape of the
initially buoyant flux ring, promoting localized rising loops. Flux tubes in
fully convective stars have a tendency to rise nearly parallel to the rotation
axis. However, the presence of strong differential rotation allows some
initially low latitude flux tubes of moderate strength to develop rising loops
that emerge in the near-equatorial region. Magnetic pumping suppresses the
global rise of the flux tube most efficiently in the deeper interior and at
lower latitudes. The results of these simulations aim to provide a link between
dynamo-generated magnetic fields, fluid motions, and observations of starspots
for fully convective stars.Comment: 20 pages, 15 figures, accepted to Astrophysical Journa
Contributions of divergent and nondivergent winds to the kinetic energy balance of a severe storm environment
Divergent and rotational components of the synoptic scale kinetic energy balance are presented using rawinsonde data at 3 and 6 h intervals from the Atmospheric Variability Experiment (AVE 4). Two intense thunderstorm complexes occurred during the period. Energy budgets are described for the entire computational region and for limited volumes that enclose and move with the convection. Although small in magnitude, the divergent wind component played an important role in the cross contour generation and horizontal flux divergence of kinetic energy. The importance of V sub D appears directly to the presence and intensity of convection within the area. Although K sub D usually comprised less than 10 percent of the total kinetic energy content within the storm environment, as much as 87 percent of the total horizontal flux divergence and 68 percent of the total cross contour generation was due to the divergent component in the upper atmosphere. Generation of kinetic energy by the divergent component appears to be a major factor in the creation of an upper level wind maximum on the poleward side of one of the complexes. A random error analysis is presented to assess confidence limits in the various energy parameters
An analytical investigation of NO sub x control techniques for methanol fueled spark ignition engines
A thermokinetic SI engine simulation was used to study the effects of simple nitrogen oxide control techniques on performance and emissions of a methanol fueled engine. As part of this simulation, a ring crevice storage model was formulated to predict UBF emissions. The study included spark retard, two methods of compression ratio increase and EGR. The study concludes that use of EGR in high turbulence, high compression engines will both maximize power and thermal efficiency while minimizing harmful exhaust pollutants
Theoretical limits on magnetic field strengths in low-mass stars
Observations have suggested that some low-mass stars have larger radii than
predicted by 1-D structure models. Some theoretical models have invoked very
strong interior magnetic fields (of order 1 MG or more) as a possible cause of
such large radii. Whether fields of that strength could in principle by
generated by dynamo action in these objects is unclear, and we do not address
the matter directly. Instead, we examine whether such fields could remain in
the interior of a low mass object for a significant time, and whether they
would have any other obvious signatures. First, we estimate timescales for the
loss of strong fields by magnetic buoyancy instabilities. We consider a range
of field strengths and simple morphologies, including both idealized flux tubes
and smooth layers of field. We confirm some of our analytical estimates using
thin flux tube magnetohydrodynamic (MHD) simulations of the rise of buoyant
fields in a fully-convective M-dwarf. Separately, we consider the Ohmic
dissipation of such fields. We find that dissipation provides a complementary
constraint to buoyancy: while small-scale, fibril fields might be regenerated
faster than they rise, the dissipative heating associated with such fields
would in some cases greatly exceed the luminosity of the star. We show how
these constraints combine to yield limits on the internal field strength and
morphology in low-mass stars. In particular, we find that for stars of 0.3
solar masses, no fields in flux tubes stronger than about 800 kG are
simultaneously consistent with both constraints.Comment: 19 pages, 10 figures, accepted to Ap
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