Tamm-Horsfall glycoprotein binds IgG with high affinity

Tamm-Horsfall glycoprotein binds IgG with high affinity. Tamm-Horsfall protein (THP), a monomelic glycoprotein (Mr 80 to 100 kDa), is produced by the mammalian kidney's thick ascending limb of Henle cells and excreted into the urine. The function of THP is uncertain. Here we report that a high molecular weight contaminant in sheep THP (sTHP) preparations was identified as sheep IgG by its positive reaction with donkey anti-sheep IgG antibody and with protein G. To answer the question of whether sTHP and sheep IgG co-purified because of a physical interaction between the two proteins, an enzyme-linked immunosorbent assay (ELISA) using immobilized sTHP and soluble sheep IgG was performed. Analysis of the ELISA data identified the presence of two sets of binding sites: a high affinity site (Kd 10-12 to 10-13 M) and a lower affinity site (Kd 10-10 to 10-11 M). The ELISA detected a similar high affinity interaction between human THP (hTHP) and human IgG. The binding of sheep IgG to immobilized sTHP was inhibited by soluble sTHP. These observations suggest an additional factor to be considered in studies addressing THP's potential immuno-regulatory function

Vendor Comparison of Video Detection Systems

Video detection has become increasingly popular for presence detection at signalized intersections because of its versatility. However, several reports have documented performance problems in specific systems. This paper quantifies the performance of three different commercially available video detection systems. The systems were tested in May and September 2005 for presence detection accuracy. Prior to the May 2005 test, a representative from each vendor configured the video detection zones to match the loop detection zone as closely as possible. The outputs from the loop detection for the through-right and left-turn lane groups were compared with the corresponding output from each of the video detection systems. Whenever there was a discrepancy between the loop and video, a digital video was observed to determine the cause of the discrepancy. Missed calls and false calls were categorized for each system. The errors were also categorized according to the impact that they would have on signal operations. During a 24hr test on two separate days, the number of missed detections longer than 5 seconds ranged from 9 to 147, and the number of false calls longer than 5 seconds ranged from 16 to 149

Cosmic Shear and Power Spectrum Normalization with the Hubble Space Telescope

Weak lensing by large-scale structure provides a direct measurement of matter fluctuations in the universe. We report a measurement of this `cosmic shear' based on 271 WFPC2 archival images from the Hubble Space Telescope Medium Deep Survey (MDS). Our measurement method and treatment of systematic effects were discussed in an earlier paper. We measure the shear variance on scales ranging from 0.7' to 1.4', with a detection significance greater than 3.8. This allows us to measure the normalization of the matter power spectrum to be sigma8 = (0.94 +/- 0.10 +/- 0.14) (0.3/Omega_m)^0.44 (0.21/Gamma)^0.15, in a LCDM universe. The first 1sigma error includes statistical errors only, while the latter also includes (gaussian) cosmic variance and the uncertainty in the galaxy redshift distribution. Our results are consistent with earlier cosmic shear measurements from the ground and from space. We compare our cosmic shear results and those from other groups to the normalization from cluster abundance and galaxy surveys. We find that the combination of four recent cosmic shear measurements are somewhat inconsistent with the recent normalization using these methods, and discuss possible explanations for the discrepancy.Comment: 4 pages, including 3 figures. Uses emulateapj. To appear in ApJL. Minor revisions to match the accepted versio

Extension rates across the northern Shanxi Grabens, China, from Quaternary geology, seismicity and geodesy

Discrepancies between geological, seismic and geodetic rates of strain can indicate that rates of crustal deformation, and hence seismic hazard, are varying through time. Previous studies in the northern Shanxi Grabens, at the northeastern corner of the Ordos Plateau in northern China, have found extension rates of anywhere between 0 and 6 mm a−1 at an azimuth of between 95° and 180°. In this paper we determine extension rates across the northern Shanxi Grabens from offset geomorphological features and a variety of Quaternary dating techniques (including new IRSL and Ar-Ar ages), a Kostrov summation using a 700 yr catalogue of historical earthquakes, and recent campaign GPS measurements. We observe good agreement between Quaternary, seismic and geodetic rates of strain, and we find that the northern Shanxi Grabens are extending at around 1–2 mm a−1 at an azimuth of ≈151°. The azimuth of extension is particularly well constrained and can be reliably inferred from catalogues of small earthquakes. We do not find evidence for any substantial variations in extension rate through time, though there is a notable seismic moment rate deficit since 1750. This deficit could indicate complex fault interactions across large regions, aseismic accommodation of deformation, or that we are quite late in the earthquake cycle with the potential for larger earthquakes in the relatively near future

Cosmic Shear and Power Spectrum Normalization with the Hubble Space Telescope

Weak lensing by large-scale structure provides a direct measurement of matter fluctuations in the universe. We report a measurement of this "cosmic shear" based on 271 Wide Field Planetary Camera 2 archival images from the Hubble Space Telescope Medium Deep Survey. Our measurement method and treatment of systematic effects were discussed in an earlier paper. We measure the shear variance on scales ranging from 07 to 14, with a detection significance greater than 3.8 σ. This allows us to measure the normalization of the matter power spectrum to be σ8 = (0.94 ± 0.10 ± 0.14)(0.3/Ωm)0.44(0.21/Γ)0.15, in a ΛCDM universe. The first 1 σ error includes statistical errors only, while the latter also includes (Gaussian) cosmic variance and the uncertainty in the galaxy redshift distribution. Our results are consistent with earlier cosmic shear measurements from the ground and from space. We compare our cosmic shear results and those from other groups to the normalization from cluster abundance and galaxy surveys. We find that the combination of four recent cosmic shear measurements are somewhat inconsistent with the recent normalization using these methods and discuss possible explanations for the discrepancy

Detection of Cosmic Shear with the HST Survey Strip

Weak lensing by large-scale structure provides a unique method to directly measure matter fluctuations in the universe, and has recently been detected from the ground. Here, we report the first detection of this `cosmic shear' based on space-based images. The detection was derived from the Hubble Space Telescope (HST) Survey Strip (or Groth Strip), a 4' by 42' set of 28 contiguous WFPC2 pointings with I<27. The small size of the HST Point-Spread Function (PSF) affords both a lower statistical noise, and a much weaker sensitivity to systematic effects, a crucial limiting factor of cosmic shear measurements. Our method and treatment of systematic effects were discussed in an earlier paper (Rhodes, Refregier & Groth 2000). We measure an rms shear of 1.8% on the WFPC2 chip scale (1.27'), in agreement with the predictions of cluster-normalized CDM models. Using a Maximum Likelihood (ML) analysis, we show that our detection is significant at the 99.5% confidence level (CL), and measure the normalization of the matter power spectrum to be sigma8*Omega_m^(0.48) = 0.51 (+0.14,-0.17), in a LambdaCDM universe. These 68% CL errors include (Gaussian) cosmic variance, systematic effects and the uncertainty in the redshift distribution of the background galaxies. Our result is consistent with earlier lensing measurements from the ground, and with the normalization derived from cluster abundance. We discuss how our measurement can be improved with the analysis of a large number of independent WFPC2 fields.Comment: 4 pages, 2 figure

Measurement of Cosmic Shear with the Space Telescope Imaging Spectrograph

Weak lensing by large-scale structure allows a direct measure of the dark matter distribution. We have used parallel images taken with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to measure weak lensing, or cosmic shear. We measure the shapes of 26036 galaxies in 1292 STIS fields and measure the shear variance at a scale of 0.51 arcminutes. The charge transfer efficiency (CTE) of STIS has degraded over time and introduces a spurious ellipticity into galaxy shapes during the readout process. We correct for this effect as a function of signal to noise and CCD position. We further show that the detected cosmic shear signal is nearly constant in time over the approximately four years of observation. We detect cosmic shear at the 5.1 sigma level, and our measurement of the shear variance is consistent with theoretical predictions in a LambdaCDM universe. This provides a measure of the normalization of the mass power spectrum sigma_8=(1.02 +- 0.16) (0.3/Omega_m)^{0.46} (0.21/Gamma)^{0.18}$. The one-sigma error includes noise, cosmic variance, systematics and the redshift uncertainty of the source galaxies. This is consistent with previous cosmic shear measurements, but tends to favor those with a high value of sigma_8. It is also consistent with the recent determination of sigma_8 from the Wilkinson Microwave Anisotropy Probe (WMAP) experiment.Comment: 9 pages, 5 figure, 1 table, Accepted to Ap

Full-disk magnetograms obtained with a Na magneto-optical filter at the Mount Wilson Observatory

The first full-disk magnetograms to be obtained with the Na magneto-optical filter (MOF) which is located at the 60 foot solar tower of the Mount Wilson Observatory are presented. This MOF was employed as a longitudinal magnetograph on June 18, 19, and July 1, 1987. On those three days the MOF was combined with a large format (1024 x 1024 pixel) virtual phase change coupled device camera and a high-speed data acquisition system. The combined system was used to record both line-of-sight magnetograms and Dopplergrams which covered the entire visible solar hemisphere. The pixel size of these magnetograms and Dopplergrams was 2.3 arcseconds. On each of the three days a time series of nine pairs of magnetograms and Dopplergrams was obtained at the rate of one pair every two minutes. On the same three day longitudinal magnetograms have one arcsecond pixels were obtained with the vacuum telescope at Kitt Peak. The MOF and vacuum tower magnetograms were compared at both the JPL Multi-Mission Image Processing Laboratory and at USC and have found the two sets of images to be well correlated both in spatial distribution and strength of the measured magnetic field. The simultaneously-obtained MOF Dopplergrams to remove the crosstalk which was present between the Doppler and Zeeman shifts of the NaD lines from the magnetograms from all three days and will also describe recent improvements to the system which allowed the obtaining of full-disk magnetograms as rapidly as one every 25 seconds