3,959 research outputs found
I Know Why You Went to the Clinic: Risks and Realization of HTTPS Traffic Analysis
Revelations of large scale electronic surveillance and data mining by
governments and corporations have fueled increased adoption of HTTPS. We
present a traffic analysis attack against over 6000 webpages spanning the HTTPS
deployments of 10 widely used, industry-leading websites in areas such as
healthcare, finance, legal services and streaming video. Our attack identifies
individual pages in the same website with 89% accuracy, exposing personal
details including medical conditions, financial and legal affairs and sexual
orientation. We examine evaluation methodology and reveal accuracy variations
as large as 18% caused by assumptions affecting caching and cookies. We present
a novel defense reducing attack accuracy to 27% with a 9% traffic increase, and
demonstrate significantly increased effectiveness of prior defenses in our
evaluation context, inclusive of enabled caching, user-specific cookies and
pages within the same website
Spectroscopic Confirmation of a Radio-Selected Galaxy Overdensity at z=1.11
We report the discovery of a galaxy overdensity at z=1.11 associated with the
z=1.110 high-redshift radio galaxy MG0442+0202. The group, CL0442+0202, was
found in a near-infrared survey of z>1 radio galaxies undertaken to identify
spatially-coincident regions with a high density of objects red in I-K' color,
typical of z>1 elliptical galaxies. Spectroscopic observations from the Keck
telescope reveal five galaxies within 35" of MG0442+0202 at 1.10<z<1.11. These
member galaxies have broad-band colors and optical spectra consistent with
passively-evolving elliptical galaxies formed at high redshift. A 45ks Chandra
X-Ray Observatory observation detects the radio galaxy and four point sources
within 15" of the radio galaxy, corresponding to a surface density two orders
of magnitude higher than average for X-ray sources at these flux levels,
S(0.5-2keV) > 5e-16 erg/cm2/s. One of these point sources is identified with a
radio-quiet, typeII quasar at z=1.863, akin to sources recently reported in
deep Chandra surveys. The limit on an extended hot intracluster medium in the
Chandra data is S(1-6keV) < 1.9e-15 erg/cm2/s (3-sigma, 30" radius aperture).
Though the X-ray observations do not confirm the existence of a massive, bound
cluster at z>1, the success of the optical/near-infrared targeting of
early-type systems near the radio galaxy validates searches using radio
galaxies as beacons for high-redshift large-scale structure. We interpret
CL0442+0202 to be a massive cluster in the process of formation.Comment: 23 pages, 7 figure
To achieve (E)quality health care for childhood cancer survivors
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111230/1/21572_ftp.pd
AAT/WFI observations of the Extragalactic H I Cloud HIPASS J1712-64
AAT/WFI optical images of a candidate extragalactic HI cloud, HIPASS
J1712-64, are presented. The g and r-band CCD mosaic camera frames were
processed using a new data pipeline recently installed at the AAO. The
resultant stacked images reach significantly deeper levels than those of
previous published optical imaging of this candidate, providing a detection
limit M_g -7 at a distance of 3Mpc, the inferred distance to HIPASS J1712-64.
However, detailed analysis of the images fails to uncover any stellar
population associated with the HI emission. If this system is a member of the
Local Group then it is pathologically different to other members. Hence, our
observations reinforce earlier suggestions that this HI cloud is most likely
Galactic in origin and not a Local Volume dwarf galaxy.Comment: 8 pages, accepted for publication in PASA (Figures reduced in
resolution, please contact gfl if you wish the higher resolution versions
Recessions and Local Labor Market Hysteresis
This paper studies the effects of each U.S. recession since 1973 on local labor markets. We find that recession-induced declines in employment are permanent, suggesting that local areas experience permanent declines in labor demand relative to less-affected areas. Population also falls, primarily due to reduced in-migration, but by less than employment. As a result, recessions generate long-lasting hysteresis: persistent decreases in the employment-to-population ratio and earnings per capita. Changes in the composition of workers explain less than half of local hysteresis. We further show that finite sample bias in vector autoregressions leads to artificial convergence, which can explain why some previous work finds no evidence of hysteresis in employment rates
Place-Based Consequences of Person-Based Transfers: Evidence from Recessions
This paper studies how government transfers respond to changes in local economic activity that emerge during recessions. Local labor markets that experience greater employment losses during recessions face persistent relative decreases in earnings per capita. However, these areas also experience persistent increases in transfers per capita, which offset 16 percent of the earnings loss on average. The increase in transfers is driven by unemployment insurance in the short run, and medical, retirement, and disability transfers in the long run. Our results show that nominally place-neutral transfer programs redistribute considerable sums of money to places with depressed economic conditions
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