NASA Earth Science Disasters Program Tropical Cyclone Response

No abstract availabl

Qualitative and Quantitative Evaluation of Indirect Immuno-fluorescent H-2 Stain on Tissue Sections

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65483/1/j.1399-0039.1979.tb00826.x.pd

Design, manufacture and characterization of an optical fiber glucose affinity sensor based on an homogeneous fluorescence energy transfer assay system

Optical fiber biosensors based on fluorescence assays have several distinct advantages when measuring biological analytes such as metabolites, cofactors, toxins, etc. Not only are optical signals immune to electronic interferences, but the polychromatic nature of most fluorochemical assays provides more potentially useful data about the system being studied. One of the most common difficulties normally encountered with optical biosensors is the inability to routinely recalibrate the optical and electronic components of the system throughout the life of the sensor. With this in mind, an optical biosensor system for glucose has been constructed along with the peripheral electronic instrumentation. The biochemical assay is based on an homogeneous singlet/singlet energy transfer affinity assay. The sensor probe indirectly measures glucose concentrations from the level of fluorescence quenching caused by the homogeneous competition assay between TRITC labeled concanavalin A (receptor) and FITC labeled Dextran (ligand). The FITC signal is used as an indicator for glucose concentrations and the TRITC signal is used for internal calibration. Chemical derivatization procedures using succinic anhydride were developed to prevent aggregation of the receptor protein in solution, and the TRITC/ConA ratios were optimized to achieve the best sensor performance. Using this sensor system, the FITC-Dextran detection limit was 0.05 [mu]g/ml and glucose concentrations up to 1600 mg/dl could be detected with a time response of approximately 10 min.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30643/1/0000285.pd

The Political Philosophy of Campaign Finance Reform as Articulated in the Dissents in Austin v. Michigan Chamber of Commerce.

The 1992 presidential candidacy of Jerry Brown, who called for campaign contribution limits, has reignited the issue of campaign finance reform. Indeed, the United States Supreme Court has recognized the importance of campaign finance reform as a judicial issue. The importance of this issue is marked by the Court’s continued willingness to address the regulation of campaign finance since the 1976 landmark case of Buckley v. Valeo. The case of Austin v. Michigan Chamber of Commerce emphasized the somewhat confused nature of the Supreme Court’s campaign finance reform decisions. The Supreme Court and state legislatures will likely continue to address the important relationship between campaign financing and political corruption. These bodies will continue to wrestle with the issues of equality in the political process. Finally, the dissenting Justices in Austin are quickly becoming representative of the Supreme Court’s majority. The Supreme Court Justices’ decision to adopt the powerful metaphor that money is speech and deserving of constitutional protection allows the Justices to appear as champions of free speech and civil liberties. The dissenting Justices in Austin, by conflating money and speech, fail to heed a distinction made by John Stuart Mill who argues the “doctrine of Free Trade … rests on grounds different from, though equally solid with, the principle of equal liberty.” Mill warned society not to confuse the regulation of the economic marketplace with the marketplace of ideas. According to Mill, to regulate trade is to limit ideas which do not harm another, but which are suppressed for their own sake. If money is allowed to commodify goods such as free speech and if society does not accept the logic found in the dissents of Austin, the political philosophies may gradually be reduced to what will be most important and unfortunate, our political philosophies of money

Fiber-optic biosensors based on fluorescence energy transfer

A new optical homogeneous biochemical method for the assay of glucose has been developed, based on fluorescence energy transfer between a glucose analog, dextran labeled with fluorescein isothiocyanate (FITC--dextran), and a glucose-receptor protein, Rhodamine-labeled Concanavalin A (Rh--ConA). When FITC--dextran binds to Rh--ConA in solution, and is light-activated, the FITC label transfers its absorbed energy to the Rhodamine label, which then emits light according to its own characteristic fluorescence spectrum. When glucose is added to this solution, the FITC fluorescence intensity increases as FITC--dextran is released from the Rh--ConA and is replaced by glucose. Thus it is possible to determine glucose concentrations directly from the level of FITC fluorescence.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27414/1/0000449.pd

Influence of ractopamine supplementation on Salmonella in feeder pigs

The objective of the current study was to determine the effect of ractopamine supplementation on gut populations and fecal shedding of Salmonella in growing pigs

Late Quaternary glacier sensitivity to temperature and precipitation distribution in the Southern Alps of New Zealand

Glaciers respond to climate variations and leave geomorphic evidence that represents an important terrestrial paleoclimate record. However, the accuracy of paleoclimate reconstructions from glacial geology is limited by the challenge of representing mountain meteorology in numerical models. Precipitation is usually treated in a simple manner and yet represents difficult-to-characterize variables such as amount, distribution, and phase. Furthermore, precipitation distributions during a glacial probably differed from present-day interglacial patterns. We applied two models to investigate glacier sensitivity to temperature and precipitation in the eastern Southern Alps of New Zealand. A 2-D model was used to quantify variations in the length of the reconstructed glaciers resulting from plausible precipitation distributions compared to variations in length resulting from change in mean annual air temperature and precipitation amount. A 1-D model was used to quantify variations in length resulting from interannual climate variability. Assuming that present-day interglacial values represent precipitation distributions during the last glacial, a range of plausible present-day precipitation distributions resulted in uncertainty in the Last Glacial Maximum length of the Pukaki Glacier of 17.1 km (24%) and the Rakaia Glacier of 9.3 km (25%), corresponding to a 0.5°C difference in temperature. Smaller changes in glacier length resulted from a 50% decrease in precipitation amount from present-day values (−14% and −18%) and from a 50% increase in precipitation amount (5% and 9%). Our results demonstrate that precipitation distribution can produce considerable variation in simulated glacier extents and that reconstructions of paleoglaciers should include this uncertainty

Polarised infrared emission from X-ray binary jets

Near-infrared (NIR) and optical polarimetric observations of a selection of X-ray binaries are presented. The targets were observed using the Very Large Telescope and the United Kingdom Infrared Telescope. We detect a significant level (3 sigma) of linear polarisation in four sources. The polarisation is found to be intrinsic (at the > 3 sigma level) in two sources; GRO J1655-40 (~ 4-7% in H and Ks-bands during an outburst) and Sco X-1 (~ 0.1-0.9% in H and K), which is stronger at lower frequencies. This is likely to be the signature of optically thin synchrotron emission from the collimated jets in these systems, whose presence indicates a partially-ordered magnetic field is present at the inner regions of the jets. In Sco X-1 the intrinsic polarisation is variable (and sometimes absent) in the H and K-bands. In the J-band (i.e. at higher frequencies) the polarisation is not significantly variable and is consistent with an interstellar origin. The optical light from GX 339-4 is also polarised, but at a level and position angle consistent with scattering by interstellar dust. The other polarised source is SS 433, which has a low level (0.5-0.8%) of J-band polarisation, likely due to local scattering. The NIR counterparts of GRO J0422+32, XTE J1118+480, 4U 0614+09 and Aql X-1 (which were all in or near quiescence) have a linear polarisation level of < 16% (3 sigma upper limit, some are < 6%). We discuss how such observations may be used to constrain the ordering of the magnetic field close to the base of the jet in such systems.Comment: Accepted to be published in MNRAS; 13 pages, 6 figure

Identification of a novel protein containing two C2 domains selectively expressed in the rat brain and kidney

AbstractWe have isolated and characterized a rat brain cDNA clone which encodes a new protein of 474 amino acids in length which contains two C2 domains structurally homologous to those present in synaptotagmins. The overall amino acid identity in C2 domains between this protein and the synaptotagmins is 36–44%. This protein also contains 3 putative consensus sequences for phosphorylation by cAMP-dependent protein kinase. RNA blot hybridization revealed a 3.0 kb transcript abundantly expressed only in the rat brain and the kidney. Thus, we called this brain/kidney protein (B/K). In situ hybridization and Northern blot analyses showed that the B/K transcript was found in forebrain including the olfactory bulb, cerebral cortex, hippocampus, and hypothalamus. In the kidney, high levels of B/K transcript were expressed in the papillary region of the inner medulla, the inner stripe of the outer medulla and the cortex. The selective expression in forebrain and kidney suggests that B/K may be involved in similar cAMP-dependent processes at these very different sites