70 research outputs found

    Discovery of a Novel Molecule that Regulates Tumor Growth and Metastasis

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    The heparan sulfate proteoglycan, Glypican-1 (GPC1), significantly impacts the growth of pancreatic cancer cells in vivo and markedly attenuates tumor angiogenesis and metastasis in athymic mice. Interestingly, both cancer cell-derived and host-derived GPC1 play an important role in tumor development and spread. These data suggest that GPC1 may be a valid therapeutic target for pancreatic cancer. KEYWORDS: Glypican-1, GPC1, pancreatic cancer, PDAC, angiogenesis, metastasis, tumor growth, microenvironment Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic and biologically aggressive malignancy that is the fourth leading cause of cancer death in the U.S. with a 5-year survival rate of less than 5%. Since PDAC is usually diagnosed at an advanced stage, after the tumor has already metastasized and is no longer operable, the number of new PDAC cases diagnosed each year is nearly equivalent to the mortality rate In a recent study published in the Journal of Clinical Investigation, it was shown that a common growth factor coreceptor, Glypican-1 (GPC1), is abnormally abundant in pancreatic cancer and that the loss of GPC1 results in reduced tumor growth, angiogenesis, and metastasi

    Early Results from NASA's Assessment of Satellite Servicing

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    Following recommendations by the NRC, NASA's FY 2008 Authorization Act and the FY 2009 and 2010 Appropriations bills directed NASA to assess the use of the human spaceflight architecture to service existing/future observatory-class scientific spacecraft. This interest in satellite servicing, with astronauts and/or with robots, reflects the success that NASA achieved with the Shuttle program and HST on behalf of the astronomical community as well as the successful construction of ISS. This study, led by NASA GSFC, will last about a year, leading to a final report to NASA and Congress in autumn 2010. We will report on its status, results from our March satellite servicing workshop, and recent concepts for serviceable scientific missions

    Wide-Field InfraRed Survey Telescope (WFIRST) Slitless Spectrometer: Design, Prototype, and Results

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    The slitless spectrometer plays an important role in the Wide-Field InfraRed Survey Telescope (WFIRST) mission for the survey of emission-line galaxies. This will be an unprecedented very wide field, HST quality 3D survey of emission line galaxies. The concept of the compound grism as a slitless spectrometer has been presented previously. The presentation briefly discusses the challenges and solutions of the optical design, and recent specification updates, as well as a brief comparison between the prototype and the latest design. However, the emphasis of this paper is the progress of the grism prototype: the fabrication and test of the complicated diffractive optical elements and powered prism, as well as grism assembly alignment and testing. Especially how to use different tools and methods, such as IR phase shift and wavelength shift interferometry, to complete the element and assembly tests. The paper also presents very encouraging results from recent element tests to assembly tests. Finally we briefly touch the path forward plan to test the spectral characteristic, such as spectral resolution and response

    Alignment and Test of the Wide Field Infrared Survey Telescope (WFIRST) Engineering Design Unit (EDU) Grism

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    The WFIRST wide field instrument (WFI) includes a slitless spectrometer, which plays an important role in the WFIRST mission for the survey of emission-line galaxies. WFI is building engineering design and environmental test (EDU and ETU) units to reduce risk for the flight grism unit. We report here on successful build and test of the EDU grism. The four-element EDU grism consists of two prism elements and two diffractive elements that provide R700 dispersion. The elements were fabricated with alignment fiducials and integral flats to allow opto-mechanical alignment in six-degrees of freedom. Each element in turn, was installed onto a hexapod and positioned to its nominal orientation relative to the grism deck, then bonded into individual cells. Alignment measurements were performed in situ using theodolites to set tip/tilt and a Micro-vu non-contact Multisensor Measurement System was used to set despace, decenter and clocking of each element using the hexapod. After opto-mechanical alignment, the grism wavefront was measured using an Infrared ZYGO interferometer at various field points extending over a 20 by 14- degree (local) field of view. Using modeled alignment sensitivities, we determined the alignment correction required on our Element 2 prism compensator and successfully minimized the field dependent wavefront error and confocality. This paper details the alignment and testing of the EDU grism at ambient and cold operating temperatures

    The First Definitive Binary Orbit Determined with the Hubble Space Telescope Fine Guidance Sensors: Wolf 1062 (Gliese 748)

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    The M dwarf binary, Wolf 1062 (Gliese 748), has been observed with the Hubble Space Telescope (HST) Fine Guidance Sensor 3 in the transfer function scan mode to determine the apparent orbit. This is the first orbit defined fully and exclusively with HST, and is the most accurate definitive orbit for any resolved, noneclipsing system. The orbital period is 2.4490 ± 0.0119 yr and the semimajor axis is 01470 ± 00007—both quantities are now known to better than 1%. Using the weighted mean of seven parallax measurements and these HST data, we find the system mass to be 0.543 ± 0.031 M⊙, where the error of 6% is due almost entirely to the parallax error. An estimated fractional mass from the infrared brightness ratio and infrared mass-luminosity relation yields a mass for the primary of 0.37 M⊙, and the secondary falls in the regime of very low mass stars, with a mass of only 0.17 M⊙

    Introduction to special issue:New Times Revisited: Britain in the 1980s

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    The authors in this volume are collectively engaged with a historical puzzle: What happens if we examine the decade once we step out of the shadows cast by Thatcher? That is, does the decade of the 1980s as a significant and meaningful periodisation (equivalent to that of the 1960s) still work if Thatcher becomes but one part of the story rather than the story itself? The essays in this collection suggest that the 1980s only makes sense as a political period. They situate the 1980s within various longer term trajectories that show the events of the decade to be as much the consequence as the cause of bigger, long-term historical processes. This introduction contextualises the collection within the wider literature, before explaining the collective and individual contributions made

    Equilibrium solutions of the restricted problem of 2+2 bodies

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    Generalizations of the Jacobian integral

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