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U.S. Commission on Immigration Reform
The U.S. Commission on Immigration Reform was created by Congress to assess U.S. immigration policy and make recommendations regarding its implementation and effects. Mandated in the Immigration Act of 1990 to submit an interim report in 1994 and a final report in 1997, the Commission has undertaken public hearings, fact-finding missions, and expert consultations to identify the major immigration-related issues facing the United States today.LBJ School of Public Affair
Interpocket polarization model for magnetic structures in rare-earth hexaborides
The origin of peculiar magnetic structures in cubic rare-earth (R)
hexaborides RB_6 is traced back to their characteristic band structure. The
three sphere-like Fermi surfaces induce interpocket polarization of the
conduction band as a part of a RKKY-type interaction. It is shown for the
free-electron-like model that the interpocket polarization gives rise to a
broad maximum in the intersite interaction I(q) around q=(1/4,1/4,1/2) in the
Brillouin zone. This maximum is consistent with the superstructure observed in
R=Ce, Gd and Dy. The wave-number dependence of I(q) is independently extracted
from analysis of the spin-wave spectrum measured for NdB_6. It is found that
I(q) obtained from fitting the data has a similarly to that derived by the
interpocket polarization model, except that the absolute maximum now occurs at
(0,0,1/2) in consistency with the A-type structure. The overall shape of I(q)
gives a hint toward understanding an incommensurate structure in PrB_6 as well.Comment: 5 pages, 3 figures, submitted to J.Phys.Soc.Jp
Modular symbols in Iwasawa theory
This survey paper is focused on a connection between the geometry of
and the arithmetic of over global fields,
for integers . For over , there is an explicit
conjecture of the third author relating the geometry of modular curves and the
arithmetic of cyclotomic fields, and it is proven in many instances by the work
of the first two authors. The paper is divided into three parts: in the first,
we explain the conjecture of the third author and the main result of the first
two authors on it. In the second, we explain an analogous conjecture and result
for over . In the third, we pose questions for general
over the rationals, imaginary quadratic fields, and global function fields.Comment: 43 page
Pragmatism, moral responsibility or policy change: the Syrian refugee crisis and selective humanitarianism in the Turkish refugee regime
Cancer in general responders participating in world trade center health programs, 2003-2013
© The Author(s) 2020. Published by Oxford University Press. Background: Following the September 11, 2001, attacks on the World Trade Center (WTC), thousands of workers were exposed to an array of toxins known to cause adverse health effects, including cancer. This study evaluates cancer incidence in the WTC Health Program General Responder Cohort occurring within 12 years post exposure. Methods: The study population consisted of 28729 members of the General Responder Cohort enrolled from cohort inception, July 2002 to December 31, 2013. Standardized incidence ratios (SIRs) were calculated with cancer case inclusion and follow-up starting post September 11, 2001 (unrestricted) and, alternatively, to account for selection bias, with case inclusion and follow-up starting 6 months after enrollment in the WTC Health Program (restricted). Case ascertainment was based on linkage with six state cancer registries. Under the restricted criterion, hazard ratios were estimated using multivariable Cox proportional hazards models for all cancer sites combined and for prostate cancer. Results: Restricted analyses identified 1072 cancers in 999 responders, with elevations in cancer incidence for all cancer sites combined (SIR = 1.09, 95% confidence interval [CI] = 1.02 to 1.16), prostate cancer (SIR = 1.25, 95% CI = 1.11 to 1.40), thyroid cancer (SIR = 2.19, 95% CI = 1.71 to 2.75), and leukemia (SIR = 1.41, 95% CI = 1.01 to 1.92). Cancer incidence was not associated with any WTC exposure index (composite or individual) for all cancer sites combined or for prostate cancer. Conclusion: Our analyses show statistically significant elevations in cancer incidence for all cancer sites combined and for prostate and thyroid cancers and leukemia. Multivariable analyses show no association with magnitude or type of exposure
Polychlorinated biphenyls and their association with survival following breast cancer
Polychlorinated biphenyls (PCBs) are hypothesized to influence breast carcinogenesis due to their persistence and potential to induce estrogenic and anti-estrogenic effects. Whether PCBs influence survival following breast cancer is unknown
On Drinfeld's universal formal group over the p -adic upper half plane
All of our results are stated for 2-dimensional modules with action by the quaternion division algebra over Q p . Drinfeld's results are true in much greater generality. We remark that our results generalize easily to the case of 2-dimensional modules with action by quaternion algebras over extensions of Q p by applying the theory of formal -modules. We suspect that Drinfeld's higher dimensional modules over are determined by formulae similar to that in Theorem 46, but with α and β generalized to moduli for higher dimensional Q p -subspaces of ; however, we have not investigated this in any detail.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46233/1/208_2005_Article_BF01443357.pd
A test of water vapor radiometer-based troposphere calibration using VLBI observations on a 21-kilometer baseline
Simultaneous very long baseline interferometry (VLBI) and water vapor radiometer (WVR) measurements on a 21 km baseline showed that calibration by WVRs removed a significant fraction of the effect of tropospheric delay fluctuations for these experiments. From comparison of the residual delay variations within scans and between scans, the total tropospheric contribution t the delay residuals for each of the three 5 to 20 hour sessions was estimated as 1, 17, and 10%, with the first value being uncertain. The observed improvement in rms residual delay from WVR calibration during these three sessions was 4, 16, and 2%, respectively. The improvement is consistent with the estimated 2 to 3 mm path delay precision of current WVRs. The VLBI measurements, of natural radio sources, were conducted in April and May 1993 at Goldstone, California. Dual-frequency (2.3 and 8.4 GHz) observations were employed to remove the effects of charged particles from the data. Measurements with co-pointed WVRs, located within 50 m of the axis of each antenna, were performed to test the ability of the WVRs to calibrate line-of-sight path delays. Factors that made WVR performance assessment difficult included (1) the fact that the level of tropospheric fluctuations was smaller than is typical for Goldstone during these experiments and (2) VLBI delay variations on longer time scales (i.e., over multiple scans) contained uncalibrated instrumental effects (probably a result of slow temperature variations in the VLBI hardware) that were larger than the tropospheric effects
Mesoscopic phase separation in La2CuO4.02 - a 139La NQR study
In crystals of La2CuO4.02 oxygen diffusion can be limited to such small
length scales, that the resulting phase separation is invisible for neutrons.
Decomposition of the 139La NQR spectra shows the existence of three different
regions, of which one orders antiferromagnetically below 17K concomitantly with
the onset of a weak superconductivity in the crystal. These regions are
compared to the macroscopic phases seen previously in the title compound and
the cluster-glass and striped phases reported for the underdoped Sr-doped
cuprates.Comment: 4 pages, RevTeX, 5 figures, to be published in PR
Pilot Study of Urinary Biomarkers of Phytoestrogens, Phthalates, and Phenols in Girls
BACKGROUND: Hormonally active environmental agents have been measured among U.S. children using exposure biomarkers in urine. However, little is known about their variation by race, age, sex, and geography, and no data exist for newly developed biomarkers. OBJECTIVE: Our goal was to characterize relevant, prevalent exposures for a study of female pubertal development. METHODS: In a pilot study among 90 girls from New York City, New York, Cincinnati, Ohio, and northern California, we measured 25 urinary analytes representing 22 separate agents from three chemical families: phytoestrogens, phthalates, and phenols. Exposures occur chiefly from the diet and from household or personal care products. RESULTS: Participants represented four racial/ethnic groups (Asian, black, Hispanic, white), with mean age of 7.77 years. Most analytes were detectable in > 94% of samples. The highest median concentrations for individual analytes in each family were for enterolactone (298 μg/L), monoethylphthalate (MEP; 83.2 μg/L), and benzophenone-3 (BP3; 14.7 μg/L). Few or no data have been reported previously for four metabolites: mono(2-ethyl-5-carboxypentyl) phthalate, triclosan, bisphenol A (BPA), and BP3; these were detected in 67–100% of samples with medians of 1.8–53.2 μg/L. After multivariate adjustment, two analytes, enterolactone and BPA, were higher among girls with body mass index < 85th reference percentile than those at or above the 85th percentile. Three phthalate metabolites differed by race/ethnicity [MEP, mono(2-ethylhexyl) phthalate, and mono-3-carboxypropylphthalate]. CONCLUSIONS: A wide spectrum of hormonally active exposure biomarkers were detectable and variable among young girls, with high maximal concentrations (> 1,000 μg/L) found for several analytes. They varied by characteristics that may be relevant to development
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