7,114 research outputs found
Exploring Characteristics of Condom Use among a College Population
The increasing lack of condom use puts young people at risk for a Sexually Transmitted Infection (STI), which can lead to long term health consequences. This study was administered within Kern County, California. Kern County ranked second worst in California for chlamydia, and fourth worst for primary and secondary syphilis (California Department of Public Health, 2018). The study used archival data from Bakersfield College, which administered the American College Health Care Administrations (ACHA) survey as a need assessments and to drive health education plans.
Bakersfield College students (N=1,483) completed the survey of which 36 questions pertained to sexual behavior and condom use. ACHA revealed that aggregated 88% of students (n=1,067) do not regularly or ever use condoms during oral sex. Similarly, 63% students (n=1,084) indicated they do not regularly or ever use condoms during vaginal sex. The study used SPSS analytics to explore condom use and characteristics (i.e, STI information received, sexual behavior, relationships, and/or race).
Chi-Square results showed there was no statistically significant difference in condom use in vaginal sex between those who received information on STIs compared to those who did not receive information. However, there was statistically significant difference in condom use for those who reported condom use during anal sex in the last 30 days and received information about STIs, χ2(1) = 4.984, p = .026. The study findings will be used to better inform health education campaigns to promote condom use among the college age population
Synthetic Spectra of Hydrodynamic Models of Type Ia Supernovae
We present detailed NLTE synthetic spectra of hydrodynamic SNe Ia models. We
make no assumptions about the form of the spectrum at the inner boundary. We
calculate both Chandrasekhar-mass deflagration models and sub-Chandrasekhar
``helium detonators.'' Gamma-ray deposition is handled in a simple, accurate
manner. We have parameterized the storage of energy that arises from the time
dependent deposition of radioactive decay energy in a reasonable manner, that
spans the expected range. We find that the Chandrasekhar-mass deflagration
model W7 of Nomoto etal shows good agreement with the observed spectra of SN
1992A and SN 1994D, particularly in the UV, where our models are expected to be
most accurate. The sub-Chandrasekhar models do not reproduce the UV deficit
observed in normal SNe Ia. They do bear some resemblance to sub-luminous SNe
Ia, but the shape of the spectra (i.e. the colors) are opposite to that of the
observed ones and the intermediate mass element lines such as Si II, and Ca II
are extremely weak, which seems to be a generic difficulty of the models.
Although the sub-Chandrasekhar models have a significant helium abundance
(unlike Chandrasekhar-mass models), helium lines are not prominent in the
spectra near maximum light and thus do not act as a spectral signature for the
progenitor.Comment: submitted to ApJ, 26 pages, 10 figures, uses LaTeX styles aasms4.sty
and natbib.sty Also available at: http://www.nhn.ou.edu/~baron
Detailed Spectral Modeling of a 3-D Pulsating Reverse Detonation Model: Too Much Nickel
We calculate detailed NLTE synthetic spectra of a Pulsating Reverse
Detonation (PRD) model, a novel explosion mechanism for Type Ia supernovae.
While the hydro models are calculated in 3-D, the spectra use an angle averaged
hydro model and thus some of the 3-D details are lost, but the overall average
should be a good representation of the average observed spectra. We study the
model at 3 epochs: maximum light, seven days prior to maximum light, and 5 days
after maximum light. At maximum the defining Si II feature is prominent, but
there is also a prominent C II feature, not usually observed in normal SNe Ia
near maximum. We compare to the early spectrum of SN 2006D which did show a
prominent C II feature, but the fit to the observations is not compelling.
Finally we compare to the post-maximum UV+optical spectrum of SN 1992A. With
the broad spectral coverage it is clear that the iron-peak elements on the
outside of the model push too much flux to the red and thus the particular PRD
realizations studied would be intrinsically far redder than observed SNe Ia. We
briefly discuss variations that could improve future PRD models.Comment: 15 pages, 4 figures, submitted to Ap
Spectral Consequences of Deviation from Spherical Composition Symmetry in Type Ia Supernovae
We investigate the prospects for constraining the maximum scale of clumping
in composition that is consistent with observed Type Ia supernova flux spectra.
Synthetic spectra generated without purely spherical composition symmetry
indicate that gross asymmetries make prominent changes to absorption features.
Motivated by this, we consider the case of a single unblended line forming in
an atmosphere with perturbations of different scales and spatial distributions.
Perturbations of about 1% of the area of the photodisk simply weaken the
absorption feature by the same amount independent of the line of sight.
Conversely, perturbations of about 10% of the area of the photodisk introduce
variation in the absorption depth which does depend on the line of sight. Thus,
1% photodisk area perturbations may be consistent with observed profile
homogeneity but 10% photodisk area perturbations can not. Based on this, we
suggest that the absence of significant variation in the depths of Si II 6355
absorption features in normal Type Ia spectra near maximum light indicates that
any composition perturbations in these events are quite small. This also
constrains future three-dimensional explosion models to produce ejecta profiles
with only small scale inhomogeneities.Comment: 11 pages, 6 figure
On the High--Velocity Ejecta of the Type Ia Supernova 1994D
Synthetic spectra generated with the parameterized supernova
synthetic-spectrum code SYNOW are compared to spectra of the Type Ia SN 1994D
that were obtained before the time of maximum brightness. Evidence is found for
the presence of two-component Fe II and Ca II features, forming in high
velocity ( \kms) and lower velocity ( \kms) matter.
Possible interpretations of these spectral splits, and implications for using
early--time spectra of SNe Ia to probe the metallicity of the progenitor white
dwarf and the nature of the nuclear burning front in the outer layers of the
explosion, are discussed.Comment: 15 pages, 3 figures, 3 tables, Astrophysical Journal, in pres
Tortious Interference: The Limits of Common Law Liability for Newsgathering
Media lawyers have recently been confronted with a relatively new source of litigation: the tort of intentional interference with contractual relations, which arises out of confidentiality agreements. In this Article, the authors identify the elements of tortious interference with contracts and examine the key issues presented when this tort is applied to newsgathering. The authors then consider a potential defense based on the First Amendment. In light of the public and constitutional interests at stake, the authors conclude that the breach of a confidentiality agreement should not sustain a tortious interference claim when the press is involved in newsgathering activity
Reading the Spectra of the Most Peculiar Type Ia Supernova 2002cx
In spite of the apparent lack of Si II and S II features in its spectra, SN
2002cx was classified as a peculiar Type Ia supernova (SN Ia) on the basis of
its overall photometric and spectroscopic behavior. Spectra obtained near
maximum light contained Fe III features, as in SN 1991T-like events, but the
blueshifts of the Fe III absorptions were exceptionally low. The luminosity
also was low. We use the supernova synthetic--spectrum code SYNOW to study line
identifications in SN 2002cx. We find that the maximum-light spectra appear to
contain weak features of Si II, S II, Si III, and Ca II, which strengthens the
connection with SN 1991T-like events. We show that later spectra, obtained 12,
25, and 56 days after maximum, consist of P-Cygni resonance-scattering features
due to permitted Fe II and Co II lines. SN 2002cx had been thought to have made
the transition from a permitted-line to a forbidden-line spectrum between 25
and 56 days. Owing to the low expansion velocities the postmaximum spectral
features are narrower and easier to identify than they are in other SNe Ia. SN
2002cx will lead to improved line identifications in other SNe Ia and clarify
when the transition from a permitted-line to a forbidden-line spectrum occurs.
In the context of current SN Ia explosion models, we suggest that the
properties of SN 2002cx may be consistent with 3D deflagration models, which
are not favored for normal SNe Ia.Comment: 21 pages including 7 figures and 4 tables; accepted by PAS
Evidence for a Spectroscopic Sequence Among SNe Ia
In this Letter we present evidence for a spectral sequence among Type Ia
supernovae (SNe Ia). The sequence is based on the systematic variation of
several features seen in the near-maximum light spectrum. This sequence is
analogous to the recently noted photometric sequence among SNe Ia which shows a
relationship between the peak brightness of a SN Ia and the shape of its light
curve. In addition to the observational evidence we present a partial
theoretical explanation for the sequence. This has been achieved by producing a
series of non-LTE synthetic spectra in which only the effective temperature is
varied. The synthetic sequence nicely reproduces most of the differences seen
in the observed one and presumably corresponds to the amount of 56Ni produced
in the explosion.Comment: To appear in Astrophysical Journal Letters, uuencoded, gzipped
postscript file, also available from http://www.nhn.uoknor.edu/~baron
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