3,480 research outputs found
Reinforcing the Educational Glass Ceiling: Divergent Paths of Women Attending For-Profit Institutions
The choice of college and careers are not simple. The choices students make when selecting a college can affect them for their entire life. Tressie Cottom (2017), in her book, Lower Ed, describes our educational journey like a stream (Cottom, 2017). We are all traveling down the stream of life, and there are rocks and forks. The question is: what diverts us on our path and where do we end up? This narrative study examines the experience of women attending For-Profit Institutions and the reasoning behind choosing to go to an FPI rather than a traditional higher education institution. The participants’ stories show that they were determined to find a better career, wanted to provide for their families, and had significant life events that changed their paths
An evaluation of two approaches for developing keyboarding skills in children with cognitive disabilities
This study examined the efficacy of two programs designed to teach keyboarding skills to school-aged children with intellectual disabilities. The study employed a mixed methods research design utilizing the number of accurate key strokes and speed in completing a task as dependent variables in the quantitative analysis. The scores used in the analysis were derived from a teacher-designed test that consisted of a timed test with students keyboarding specific sets of letter sequences. The qualitative segment of the study consisted of focus group interviews with the participating teachers to determine the method perceived to be effective in teaching keyboarding skills to children with intellectual disabilities. Decisional statistics were performed to determine which program was more effective in teaching the selected students keyboarding skills. Teachers were interviewed in focus sessions and the results from the interviews were analyzed to determine their perceptions of the two programs. Overall, both programs were successful in teaching keyboarding skills; however, teachers stated that ColorCoded Keyboarding© was more effective in increasing the number of keys learned and promoting self-esteem and self-efficacy
The sources of sex differences in aging in annual fishes
Intersexual differences in life span (age at death) and aging (increase in mortality risk associated with functional deterioration) are widespread among animals, from nematodes to humans. Males often live shorter than females, but there is substantial unexplained variation among species and populations. Despite extensive research, it is poorly understood how life span differences between the sexes are modulated by an interplay among genetic, environmental and social factors. The goal of our study was to test how sex differences in life span and ageing are modulated by social and environmental factors, and by intrinsic differences between males and females. To disentangle the complex basis of sex differences in life span and aging, we combined comparative data from sex ratios in 367 natural populations of four species of African annual killifish with experimental results on sex differences in life span and aging from eight laboratory populations tested in treatments that varied social and environmental conditions. In the wild, females consistently outlived males. In captivity, sex-specific mortality depended on social conditions. In social-housed experimental groups, male-biased mortality persisted in two aggressive species, but ceased in two placid species. When social and physical contacts were prevented by housing all fish individually, male-biased mortality ceased in all four species. This outcome held across benign and challenging environmental conditions. Fitting demographic survival models revealed that increased baseline mortality was primarily responsible for a shorter male life span in social-housing conditions. The timing and rate of aging were not different between the sexes. No marker of functional aging we recorded in our study (lipofuscin accumulation, proliferative changes in kidney and liver) differed between males and females, despite their previously confirmed association with functional aging in Nothobranchius killifish. We show that sex differences in life span and aging in killifish are driven by a combination of social and environmental conditions, rather than differential functional aging. They are primarily linked to sexual selection but precipitated through multiple processes (predation, social interference). This demonstrates how sex-specific mortality varies among species even within an ecologically and evolutionary discrete lineage and explains how external factors mediate this difference
Reconstruction of the optical potential from scattering data
We propose a method for reconstruction of the optical potential from
scattering data. The algorithm is a two-step procedure. In the first step the
real part of the potential is determined analytically via solution of the
Marchenko equation. At this point we use a diagonal Pad\'{e} approximant of the
corresponding unitary -matrix. In the second step the imaginary part of the
potential is determined via the phase equation of the variable phase approach.
We assume that the real and the imaginary parts of the optical potential are
proportional. We use the phase equation to calculate the proportionality
coefficient. A numerical algorithm is developed for a single and for coupled
partial waves. The developed procedure is applied to analysis of
, , and data.Comment: 26 pages, 8 figures, results of nucl-th/0410092 are refined, some new
results are presente
Analyzing Femorotibial Cartilage Thickness Using Anatomically Standardized Maps: Reproducibility and Reference Data.
Alterations in cartilage thickness (CTh) are a hallmark of knee osteoarthritis, which remain difficult to characterize at high resolution, even with modern magnetic resonance imaging (MRI), due to a paucity of standardization tools. This study aimed to assess a computational anatomy method producing standardized two-dimensional femorotibial CTh maps. The method was assessed with twenty knees, processed following three common experimental scenarios. Cartilage thickness maps were obtained for the femorotibial cartilages by reconstructing bone and cartilage mesh models in tree-dimension, calculating three-dimensional CTh maps, and anatomically standardizing the maps. The intra-operator accuracy (median (interquartile range, IQR) of -0.006 (0.045) mm), precision (0.152 (0.070) mm), entropy (7.02 (0.71) and agreement (0.975 (0.020))) results suggested that the method is adequate to capture the spatial variations in CTh and compare knees at varying osteoarthritis stages. The lower inter-operator precision (0.496 (0.132) mm) and agreement (0.808 (0.108)) indicate a possible loss of sensitivity to detect differences in a setting with multiple operators. The results confirmed the promising potential of anatomically standardized maps, with the lower inter-operator reproducibility stressing the need to coordinate operators. This study also provided essential reference data and indications for future research using CTh maps
An Alternative Yukawa Unified SUSY Scenario
Supersymmetric SO(10) Grand Unified Theories with Yukawa unification
represent an appealing possibility for physics beyond the Standard Model.
However Yukawa unification is made difficult by large threshold corrections to
the bottom mass. Generally one is led to consider models where the sfermion
masses are large in order to suppress these corrections. Here we present
another possibility, in which the top and bottom GUT scale Yukawa couplings are
equal to a component of the charged lepton Yukawa matrix at the GUT scale in a
basis where this matrix is not diagonal. Physically, this weak eigenstate
Yukawa unification scenario corresponds to the case where the charged leptons
that are in the 16 of SO(10) containing the top and bottom quarks mix with
their counterparts in another SO(10) multiplet. Diagonalizing the resulting
Yukawa matrix introduces mixings in the neutrino sector. Specifically we find
that for a large region of parameter space with relatively light sparticles,
and which has not been ruled out by current LHC or other data, the mixing
induced in the neutrino sector is such that , in
agreement with data. The phenomenological implications are analyzed in some
detail.Comment: 32 pages, 22 Figure
Reconciling Neutralino Relic Density with Yukawa Unified Supersymmetric Models
Supersymmetric grand unified models based on the gauge group SO(10) are
especially attractive in light of recent data on neutrino masses. The simplest
SO(10) SUSY GUT models predict unification of third generation Yukawa couplings
in addition to the usual gauge coupling unification. Recent surveys of Yukawa
unified SUSY GUT models predict an inverted scalar mass hierarchy in the
spectrum of sparticle masses if the superpotential mu term is positive. In
general, such models tend to predict an overabundance of dark matter in the
universe. We survey several solutions to the dark matter problem in Yukawa
unified supersymmetric models. One solution-- lowering the GUT scale mass value
of first and second generation scalars-- leads to u_R and c_R squark masses in
the 90-120 GeV regime, which should be accessible to Fermilab Tevatron
experiments. We also examine relaxing gaugino mass universality which may solve
the relic density problem by having neutralino annihilations via the Z or h
resonances, or by having a wino-like LSP.Comment: 21 page file plus 9 figures; updated version to coincide with
published versio
Symmetric Textures in SO(10) and LMA Solution for Solar Neutrinos
We analyze a model based on SUSY SO(10) combined with SU(2) family symmetry
and symmetric mass matrices constructed by the authors recently. Previously,
only the parameter space for the LOW and vacuum oscillation (VO) solutions was
investigated. We indicate in this note the parameter space which leads to large
mixing angle (LMA) solution to the solar neutrino problem with a slightly
modified effective neutrino mass matrix. The symmetric mass textures arising
from the left-right symmetry breaking and the SU(2) symmetry breaking give rise
to very good predictions for the quark and lepton masses and mixing angles. The
prediction of our model for the |U_{e\nu_{3}}| element in the
Maki-Nakagawa-Sakata (MNS) matrix is close to the sensitivity of current
experiments; thus the validity of our model can be tested in the near future.
We also investigate the correlation between the |U_{e\nu_{3}}| element and
\tan^{2}\theta_{\odot} in a general two-zero neutrino mass texture.Comment: RevTeX4; 9 pages; 1 figur
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