2,179 research outputs found

    A Study on the Analytical Sensitivity of 6 BSE Tests Used by the Canadian BSE Reference Laboratory

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    Bovine spongiform encephalopathy (BSE) surveillance programs have been employed in numerous countries to monitor BSE prevalence and to protect animal and human health. Since 1999, the European Commission (EC) authorized the evaluation and approval of 20 molecular based tests for the rapid detection of the pathological prion protein (PrPsc) in BSE infection. The diagnostic sensitivity, convenience, and speed of these tests have made molecular diagnostics the preferred method for BSE surveillance. The aim of this study was to determine the analytical sensitivity of 4 commercially available BSE rapid-test kits, including the Prionics®-Check WESTERN, the Prionics® Check-PrioSTRIP™, the BioRad® TeSeE™ ELISA, and the IDEXX® HerdChek™ EIA. Performances of these tests were then compared to 2 confirmatory tests, including the BioRad® TeSeE™ Western Blot and the modified Scrapie Associated Fibrils (SAF)/OIE Immunoblot. One 50% w/v homogenate was made from experimentally generated C-type BSE brain tissues in ddH2O. Homogenates were diluted through a background of BSE-negative brainstem homogenate. Masses of both positive and negative tissues in each dilution were calculated to maintain the appropriate tissue amounts for each test platform. Specific concentrated homogenization buffer was added accordingly to maintain the correct buffer condition for each test. ELISA-based tests were evaluated using their respective software/detection platforms. Blot-protocols were evaluated by manual measurements of blot signal density. Detection limitations were determined by fitted curves intersecting the manufacturers' positive/negative criteria. The confirmatory SAF Immunoblot displayed the highest analytical sensitivity, followed by the IDEXX® HerdChek™ EIA, Bio-Rad® TeSeE™ Western Blot, the Bio-Rad® TeSeE™ ELISA, Prionics®-Check PrioSTRIP™, and Prionics®-Check WESTERN™, respectively. Although the tests performed at different levels of sensitivity, the most sensitive and least sensitive of the rapid tests were separated by 2 logs in analytical sensitivity, meeting European performance requirements. All rapid tests appear suitable for targeted BSE surveillance programs, as implemented in Canada

    The NASA-UC Eta-Earth Program: II. A Planet Orbiting HD 156668 with a Minimum Mass of Four Earth Masses

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    We report the discovery of HD 156668b, an extrasolar planet with a minimum mass of M_P sin i = 4.15 M_Earth. This planet was discovered through Keplerian modeling of precise radial velocities from Keck-HIRES and is the second super-Earth to emerge from the NASA-UC Eta-Earth Survey. The best-fit orbit is consistent with circular and has a period of P = 4.6455 d. The Doppler semi-amplitude of this planet, K = 1.89 m/s, is among the lowest ever detected, on par with the detection of GJ 581e using HARPS. A longer period (P ~ 2.3 yr), low-amplitude signal of unknown origin was also detected in the radial velocities and was filtered out of the data while fitting the short-period planet. Additional data are required to determine if the long-period signal is due to a second planet, stellar activity, or another source. Photometric observations using the Automated Photometric Telescopes at Fairborn Observatory show that HD 156668 (an old, quiet K3 dwarf) is photometrically constant over the radial velocity period to 0.1 mmag, supporting the existence of the planet. No transits were detected down to a photometric limit of ~3 mmag, ruling out transiting planets dominated by extremely bloated atmospheres, but not precluding a transiting solid/liquid planet with a modest atmosphere.Comment: This planet was announced at the 2010 AAS meeting in Wash. DC; 12 pages, 8 figures, 3 tables, submitted to Ap

    The NASA-UC Eta-Earth Program: III. A Super-Earth orbiting HD 97658 and a Neptune-mass planet orbiting Gl 785

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    We report the discovery of planets orbiting two bright, nearby early K dwarf stars, HD 97658 and Gl 785. These planets were detected by Keplerian modelling of radial velocities measured with Keck-HIRES for the NASA-UC Eta-Earth Survey. HD 97658 b is a close-in super-Earth with minimum mass Msini = 8.2 +/- 1.2 M_Earth, orbital period P = 9.494 +/- 0.005 d, and an orbit that is consistent with circular. Gl 785 b is a Neptune-mass planet with Msini = 21.6 +/- 2.0 M_Earth, P = 74.39 +/- 0.12 d, and orbital eccentricity 0.30 +/- 0.09. Photometric observations with the T12 0.8 m automatic photometric telescope at Fairborn Observatory show that HD 97658 is photometrically constant at the radial velocity period to 0.09 mmag, supporting the existence of the planet.Comment: Submitted to ApJ, 7 pages, 6 figures, 5 table

    Orbital Orientations of Exoplanets: HAT-P-4b is Prograde and HAT-P-14b is Retrograde

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    We present observations of the Rossiter-McLaughlin effect for two exoplanetary systems, revealing the orientations of their orbits relative to the rotation axes of their parent stars. HAT-P-4b is prograde, with a sky-projected spin-orbit angle of lambda = -4.9 +/- 11.9 degrees. In contrast, HAT-P-14b is retrograde, with lambda = 189.1 +/- 5.1 degrees. These results conform with a previously noted pattern among the stellar hosts of close-in giant planets: hotter stars have a wide range of obliquities and cooler stars have low obliquities. This, in turn, suggests that three-body dynamics and tidal dissipation are responsible for the short-period orbits of many exoplanets. In addition, our data revealed a third body in the HAT-P-4 system, which could be a second planet or a companion star.Comment: AJ, in press [8 pages

    The Vehicle, Spring 1983

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    Vol. 24, No. 2 Table of Contents A-B-C-D-E-F-G-H....Beth Kennypage 1 Contemporary IssuesBrook Wilsonpage 1 BlackJohn Stockmanpage 2 BeatGraham Lewispage 2 Catholic DazeSuzanne Hornpage 4 AfricaGraham Lewispage 5 The Friendly SkiesRajendra Sinhanpage 5 BreadKen Kempckepage 7 PhotographLinda Fraembspage 8 SnapshotMaggie Kennedypage 9 PoemAnne Smithpage 9 Activities on IceKerri Mahatpage 11 Beecham\u27s Orchard And VineyardBecky Lawsonpage 11 PoemKarri Mahatpage 12 Sneak PreviewsMaggie Kennedypage 12 ZooKen Kempckepage 12 PhotographNick Haskettpage 13 The Slave HouseCraig Barnespage 13 The Nomad Preacher\u27s SermonStacey Flanniganpage 16 Owl Creek RevisitedScott Graypage 16 Thought On CopperGraham Lewispage 20 OutfielderKen Kempckepage 20 HoneymoonJohn Stockmanpage 21 Candy Wrapper Dream GirlStacey Flanniganpage 21 PhotographLinda Fraembspage 22 October DreamMarlene Weekspage 23 IndistinctionStacey Flanniganpage 24 Taking InventorySara Farrispage 24 Flying In From K-Mart, NebraskaMichelle Mitchellpage 25 PhotographNick Haskettpage 26 Bone ChinaMichelle Mitchellpage 27 She Was A DollNick Haskettpage 30 The Seventh DayGeoffrey Andrespage 31 Blade Of Grass (On A Golf Course)Ken Kempckepage 31 PoemKen Kempckepage 32 Cigarette SmokeJean M. Davispage 33 Future LoveR. Lawsonpage 34 PhotographNick Haskettpage 35 Dancing In The StreetBetsy Acklinpage 35 PhotographLinda Fraembspage 38 CleoMarlene Weekspage 39 Teddy BearKen Kempckepage 39 PreludeBecky Lawsonpage 40https://thekeep.eiu.edu/vehicle/1043/thumbnail.jp

    M2K: II. A Triple-Planet System Orbiting HIP 57274

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    Doppler observations from Keck Observatory have revealed a triple planet system orbiting the nearby mid-type K dwarf, HIP 57274. The inner planet, HIP 57274b, is a super-Earth with \msini\ = 11.6 \mearth (0.036 \mjup), an orbital period of 8.135 Âą\pm 0.004 d, and slightly eccentric orbit e=0.19Âą0.1e=0.19 \pm 0.1. We calculate a transit probability of 6.5% for the inner planet. The second planet has \msini\ = 0.4 \mjup\ with an orbital period of 32.0 Âą0.02\pm 0.02 d in a nearly circular orbit, and e=0.05Âą0.03e = 0.05 \pm 0.03. The third planet has \msini\ = 0.53 \mjup\ with an orbital period of 432 Âą8\pm 8 d (1.18 years) and an eccentricity e=0.23Âą0.03e = 0.23 \pm 0.03. This discovery adds to the number of super Earth mass planets with \msini < 12 \mearth\ that have been detected with Doppler surveys. We find that 56 Âą18\pm 18% super-Earths are members of multi-planet systems. This is certainly a lower limit because of observational detectability limits, yet significantly higher than the fraction of Jupiter mass exoplanets, 20Âą820 \pm 8%, that are members of Doppler-detected, multi-planet systems.Comment: 11 figures, submitte to ApJ on Sept 10, 201

    Res Medica, Autumn 1959, Volume 2, Number 1

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    TABLE OF CONTENTSSYLLABUS FOR THE 223RD SESSIONHYPOTENSIVE DRUGS: G. E. Mawer, B.ScAN OCULIST LOOKS ATENDOCRINE EXOPHTHALMOS: C. R. S. Jackson.M.A., M.D., D.O.M .S., F.R.C.S.E.RES MEDICA THE TREATMENT OF CANCER: John McKendrick,M.B., Ch.B.DOCTORS AND ARTISTS: Professor W. I. C.Morris, F.R.C.S.E.SOME ASPECTS OFRHEUMATIC FEVER: David J. ClarkABDOMINAL PAIN: Geoffrey T. Millar,M.B., Ch.B.TWO HUNDRED YEARS AGO: James A. Gray, M.B..Ch.B

    The PTF Orion Project: a Possible Planet Transiting a T-Tauri Star

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    We report observations of a possible young transiting planet orbiting a previously known weak-lined T-Tauri star in the 7-10 Myr old Orion-OB1a/25-Ori region. The candidate was found as part of the Palomar Transient Factory (PTF) Orion project. It has a photometric transit period of 0.448413 +- 0.000040 days, and appears in both 2009 and 2010 PTF data. Follow-up low-precision radial velocity (RV) observations and adaptive optics imaging suggest that the star is not an eclipsing binary, and that it is unlikely that a background source is blended with the target and mimicking the observed transit. RV observations with the Hobby-Eberly and Keck telescopes yield an RV that has the same period as the photometric event, but is offset in phase from the transit center by approximately -0.22 periods. The amplitude (half range) of the RV variations is 2.4 km/s and is comparable with the expected RV amplitude that stellar spots could induce. The RV curve is likely dominated by stellar spot modulation and provides an upper limit to the projected companion mass of M_p sin i_orb < 4.8 +- 1.2 M_Jup; when combined with the orbital inclination, i orb, of the candidate planet from modeling of the transit light curve, we find an upper limit on the mass of the planetary candidate of M_p < 5.5 +- 1.4 M_Jup. This limit implies that the planet is orbiting close to, if not inside, its Roche limiting orbital radius, so that it may be undergoing active mass loss and evaporation.Comment: Corrected typos, minor clarifications; minor updates/corrections to affiliations and bibliography. 35 pages, 10 figures, 3 tables. Accepted to Ap

    Ernst Freund as Precursor of the Rational Study of Corporate Law

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    Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe

    Tolerogenic immunosuppression for organ transplantation

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    Background: Insight into the mechanisms of organ engraftment and acquired tolerance has made it possible to facilitate these mechanisms, by tailoring the timing and dosage of immunosuppression in accordance with two therapeutic principles: recipient pretreatment, and minimum use of post-transplant immunosuppression. We aimed to apply these principles in recipients of renal and extrarenal organ transplants. Methods: 82 patients awaiting kidney, liver, pancreas, or intestinal transplantation were pretreated with about 5 mg/kg of a broadly reacting rabbit antithymocyte globulin during several hours. Post-transplant immunosuppression was restricted to tacrolimus unless additional drugs were needed to treat breakthrough rejection. After 4 months, patients on tacrolimus monotherapy were considered for dose-spacing to every other day or longer intervals. Findings: We frequently saw evidence of immune activation in graft biopsy samples, but unless this was associated with graft dysfunction or serious immune destruction, treatment usually was not intensified. Immunosuppression-related morbidity was virtually eliminated. 78 (95%) of 82 patients survived at 1 year and at 13-18 months. Graft survival was 73 (89%) of 82 at 1 year and 72 (88%) of 82 at 13-18 months. Of the 72 recipients with surviving grafts, 43 are on spaced doses of tacrolimus monotherapy: every other day (n=6), three times per week (11), twice per week (15), or once per week (11). Interpretation: The striking ability to wean immunosuppression in these recipients indicates variable induction of tolerance. The simple therapeutic principles are neither drug-specific nor organ-specific. Systematic application of these principles should allow improvements in quality of life and long-term survival after organ transplantation
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