Anion transporter: highly cell-type-specific expression of distinct polypeptides and transcripts in erythroid and nonerythroid cells

Affinity-purified antibodies and cDNA probes specific for the chicken erythrocyte anion transporter (also referred to as band 3) have been used to demonstrate that this protein is expressed in a highly cell- type-specific manner in the avian kidney. Indirect immunofluorescence analysis indicates that this polypeptide is present in only a small subset of total kidney cells and is predominantly localized to the proximal convoluted tubule of this organ. Chicken erythrocytes synthesize and accumulate two structurally and serologically related band 3 polypeptides. The polypeptide that accumulates in kidney membranes has an apparent molecular weight greater than either of its erythroid counterparts. This diversity is also reflected at the RNA level, as the single band 3 mRNA species detected during various stages of erythroid development is distinct in size from that found in kidney cells. Genomic DNA blot analysis suggests that both the erythroid and kidney band 3 RNAs arise from a single gene. Furthermore, of the adult tissues we have examined that are known to express ankyrin and spectrin polypeptides, only kidney accumulates detectable levels of the band 3 mRNA and polypeptide. These observations suggest that a subset of kidney cells use an anion transport mechanism analogous to that of erythrocytes and that band 3 is expressed in a noncoordinate manner with other components of the erythroid membrane skeleton in nonerythroid cells

Balancing Justice Needs and Private Property in Constitutional Takings Provisions: A Comparative Assessment of India, Australia, and the United States

This Article explores the relationship between justice needs and private property in the constitutional takings provisions of the Indian, Australian, and American constitutions. Building upon established scholarship, it develops a theoretical framework within which to consider the way in which a state balances the requirement to provide minimal levels of justice for its citizens through the re-distribution of goods and resources with the need to protect the private property of individuals. We summarize this framework in what we refer to as the “Justice Needs-Protection of Private Property Continuum.” Using the framework developed, the Article provides an outline of the takings provisions found in the Indian, Australian, and American constitutions. Part I examines Article 300A of the Constitution of India, which contains the scope of the power of compulsory acquisition exercised by the Indian state. Part II assesses Section 51(xxxi) of the Australian Constitution which, unlike its American and Indian counterparts, operates as both a grant of power to the federal government, as well as a limitation imposed upon that power, which may, it seems, operate so as to provide some minimal protection for individual private property interests. Part III considers the Takings Clause of the Fifth Amendment to the United States Constitution which, as interpreted by the Supreme Court, provides perhaps the most robust means among the three jurisdictions considered for protecting the individual private property interests as against state takings. The Conclusion offers comparative reflections on the nature of the takings provision found in each jurisdiction.Krithika Ashok, Paul T. Babie, & John V. Ort

The Low-Redshift Intergalactic Medium

The low-redshift Ly-alpha forest of absorption lines provides a probe of large-scale baryonic structures in the intergalactic medium, some of which may be remnants of physical conditions set up during the epoch of galaxy formation. We discuss our recent Hubble Space Telescope (HST) observations and interpretation of low-z Ly-alpha clouds toward nearby Seyferts and QSOs, including their frequency, space density, estimated mass, association with galaxies, and contribution to Omega-baryon. Our HST/GHRS detections of 70 Ly-alpha absorbers with N_HI > 10^12.6 cm-2 along 11 sightlines covering pathlength Delta(cz) = 114,000 km/s show f(>N_HI) ~ N_HI^{-0.63 +- 0.04} and a line frequency dN/dz = 200 +- 40 for N_HI > 10^12.6 cm-2 (one every 1500 km/s of redshift). A group of strong absorbers toward PKS 2155-304 may be associated with gas (400-800) h_75^-1 kpc from 4 large galaxies, with low metallicity (< 0.003 solar) and D/H < 2 x 10^-4. At low-z, we derive a metagalactic ionizing radiation field from AGN of J_0 = 1.3^{+0.8 -0.5} x 10^-23 ergs/cm2/s/Hz/sr and a Ly-alpha-forest baryon density Omega-baryon = (0.008 +- 0.004) h_75^-1 [J_-23 N_14 b_100]^{1/2} For clouds of characteristic size b = (100 kpc)b_100.Comment: 5 figure

Keck constraints on a varying fine-structure constant: wavelength calibration errors

The Keck telescope's HIRES spectrograph has previously provided evidence for a smaller fine-structure constant, alpha, compared to the current laboratory value, in a sample of 143 quasar absorption systems: da/a=(-0.57+/-0.11)x10^{-5}. This was based on a variety of metal-ion transitions which, if alpha varies, experience different relative velocity shifts. This result is yet to be robustly contradicted, or confirmed, by measurements on other telescopes and spectrographs; it remains crucial to do so. It is also important to consider new possible instrumental systematic effects which may explain the Keck/HIRES results. Griest et al. (2009, arXiv:0904.4725v1) recently identified distortions in the echelle order wavelength scales of HIRES with typical amplitudes +/-250m/s. Here we investigate the effect such distortions may have had on the Keck/HIRES varying alpha results. We demonstrate that they cause a random effect on da/a from absorber to absorber because the systems are at different redshifts, placing the relevant absorption lines at different positions in different echelle orders. The typical magnitude of the effect on da/a is ~0.4x10^{-5} per absorber which, compared to the median error on da/a in the sample, ~1.9x10^{-5}, is relatively small. Consequently, the weighted mean value changes by less than 0.05x10^{-5} if the corrections we calculate are applied. Nevertheless, we urge caution, particularly for analyses aiming to achieve high precision da/a measurements on individual systems or small samples, that a much more detailed understanding of such intra-order distortions and their dependence on observational parameters is important if they are to be avoided or modelled reliably. [Abridged]Comment: 9 pages, 2 figures, 2 tables. Invited contribution to Proc. IAU XXVIIth General Assembly, Joint Discussion 9, "Are the fundamental constants varying with time?". To appear in P. Molaro, E. Vangioni-Flam, eds, Memorie della Societa Astronomica Italiana (MmSAIt), Vol. 80. Complete version of Table 1 available at http://astronomy.swin.edu.au/~mmurphy/pub.htm

The X-ray Properties of Low-Frequency Quasi-Periodic Oscillations from GRS 1915+105 up to 120 keV

We present a study of the properties of strong 0.8-3.0 Hz quasi-periodic oscillations (QPOs) that occurred during 1997 RXTE observations of the microquasar GRS 1915+105 in the low-hard state. The high count rates allow us to track individual QPO peaks, and we exploit this to develop a QPO folding technique. In contrast to previous QPO studies with RXTE, we emphasize the high energy QPO properties and report the detection of a QPO in the 60-124 keV energy band. Our technique allows us, for the first time, to measure the phase of the QPO harmonics relative to the fundamental. Variation in this phase difference leads to changes in the shape of the QPO profile with energy and over time. The strength of the QPO fundamental increases up to 19 keV, but the data do not suggest that the strength continues to increase above this energy. In some cases, the QPO amplitudes in the 30-60 keV and 60-124 keV energy bands are significantly less than in the 13-19 keV and 19-29 keV energy bands. We also use our technique to measure the phase lag of the QPO fundamental and harmonics. In the case where negative phase lags are detected for the fundamental, positive phase lags are detected for the first harmonic.Comment: Submitted to ApJ, Refereed, 9 page

Anomalies, Unparticles, and Seiberg Duality

We calculate triangle anomalies for fermions with non-canonical scaling dimensions. The most well known example of such fermions (aka unfermions) occurs in Seiberg duality where the matching of anomalies (including mesinos with scaling dimensions between 3/2 and 5/2) is a crucial test of duality. By weakly gauging the non-local action for an unfermion, we calculate the one-loop three-current amplitude. Despite the fact that there are more graphs with more complicated propagators and vertices, we find that the calculation can be completed in a way that nearly parallels the usual case. We show that the anomaly factor for fermionic unparticles is independent of the scaling dimension and identical to that for ordinary fermions. This can be viewed as a confirmation that unparticle actions correctly capture the physics of conformal fixed point theories like Banks-Zaks or SUSY QCD.Comment: 13 pages, 1 figur