42 research outputs found
Implementation of Congressional Intent: A Study of Amnesty Policy and the Immigration and Naturalization Service
In 1990, the United States Border Patrol arrested approximately one million illegals (Dillin, 1990). Significant as this number may seem, it parallels the rate of arrest that existed prior to the passage of the Immigration and Control Act of 1986 (IRCA). This phenomenon suggests that the Act has failed to accomplish one of its primary objectives: to control illegal immigration to the United States.
The IRCA represented the first major change in US immigration policy in twenty-two years. In seeking to prevent illegal entry and to gain control over the undocumented population already in the country, it contained two key provisions. First, it sanctioned fines, prison terms, or both, against employers who knowingly hire illegal aliens. The intent of Congress was clear: to use employer sanctions to reduce the “pull” or attractiveness of American jobs to aliens contemplating illegal entry into the country
Stochastic `Beads on a String' in the Accretion Tail of Arp 285
We present Spitzer infrared, GALEX UV, and SDSS and SARA optical images of
the peculiar interacting galaxy pair Arp 285 (NGC 2856/4), and compare with a
new numerical model of the interaction. We estimate the ages of clumps of star
formation in these galaxies using population synthesis models, carefully
considering the uncertainties on these ages. This system contains a striking
example of `beads on a string': a series of star formation complexes ~1 kpc
apart. These `beads' are found in a tail-like feature that is perpendicular to
the disk of NGC 2856, which implies that it was formed from material accreted
from the companion NGC 2854. The extreme blueness of the optical/UV colors and
redness of the mid-infrared colors implies very young stellar ages (~4 - 20
Myrs) for these star forming regions. Spectral decomposition of these `beads'
shows excess emission above the modeled stellar continuum in the 3.6 micron and
4.5 micron bands, indicating either contributions from interstellar matter to
these fluxes or a second older stellar population. These clumps have -12.0 <
M(B) < -10.6, thus they are less luminous than most dwarf galaxies. Our model
suggests that bridge material falling into the potential of the companion
overshoots the companion. The gas then piles up at apo-galacticon before
falling back onto the companion, and star formation occurs in the pile-up. A
luminous (M(B) ~ -13.6) extended (FWHM ~ 1.3 kpc) `bright spot' is visible at
the northwestern edge of the NGC 2856 disk, with an intermediate stellar
population (400 - 1500 Myrs). Our model suggests that this feature is part of a
expanding ripple-like `arc' created by an off-center ring-galaxy-like collision
between the two disks.Comment: Accepted by the Astronomical Journal. For color figures and appendix
material, go
tohttp://www.etsu.edu/physics/bsmith/research/sg/arp285/arp285.htm
Consistent assignment of the vibrations of symmetric and asymmetric para-disubstituted benzene molecules
We give a description of the phenyl-ring-localized vibrational modes of the ground states of the para-disubstituted benzene molecules including both symmetric and asymmetric cases. In line with others, we quickly conclude that the use of Wilson mode labels is misleading and ambiguous; we conclude the same regarding the related ones of Varsányi. Instead we label the modes consistently based upon the Mulliken (Herzberg) method for the modes of para-difluorobenzene (pDFB). Since we wish the labelling scheme to cover both symmetrically- and asymmetrically-substituted molecules, we apply the Mulliken labelling under C2v symmetry. By studying the variation of the vibrational wavenumbers with mass of the substituent, we are able to identify the corresponding modes across a wide range of molecules and hence provide consistent assignments. Particularly interesting are pairs of vibrations that evolve from in- and out-of-phase motions in pDFB to more localized modes in asymmetric molecules. We consider the para isomers of the following: the symmetric dihalobenzenes, xylene, hydroquinone, the asymmetric dihalobenzenes, halotoluenes, halophenols and cresol
Galaxy Zoo: Quantifying Morphological Indicators of Galaxy Interaction
We use Galaxy Zoo 2 visual classifications to study the morphological
signatures of interaction between similar-mass galaxy pairs in the Sloan
Digital Sky Survey. We find that many observable features correlate with
projected pair separation; not only obvious indicators of merging, disturbance
and tidal tails, but also more regular features, such as spiral arms and bars.
These trends are robustly quantified, using a control sample to account for
observational biases, producing measurements of the strength and separation
scale of various morphological responses to pair interaction. For example, we
find that the presence of spiral features is enhanced at scales < 70 h^-1 kpc,
probably due to both increased star formation and the formation of tidal tails.
On the other hand, the likelihood of identifying a bar decreases significantly
in pairs with separations < 30 h^-1 kpc, suggesting that bars are suppressed by
close interactions between galaxies of similar mass. We go on to show how
morphological indicators of physical interactions provide a way of
significantly refining standard estimates for the frequency of close pair
interactions, based on velocity offset and projected separation. The presence
of loosely wound spiral arms is found to be a particularly reliable signal of
an interaction, for projected pair separations up to ~100 h^-1 kpc. We use this
indicator to demonstrate our method, constraining the fraction of low-redshift
galaxies in truly interacting pairs, with M_* > 10^9.5 M_Sun and mass ratio <
4, to be between 0.4 - 2.7 per cent.Comment: Accepted to MNRAS on November 12, 201
Enthalpy of solvation correlations for organic solutes and gases dissolved in 1-propanol and tetrahydrofuran
This article discusses the enthalpy of solvation correlations for organic solutes and gases dissolved in 1-propanol and tetrahydrofuran
Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease
BACKGROUND:
Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes.
METHODS:
We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization.
RESULTS:
During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events.
CONCLUSIONS:
Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)