147 research outputs found

    Cyclotron tests to determine the response of solid-state detectors to protons of energies 50 to 160 mev for use in a proton spectrometer

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    Cyclotron tests for determination of solid state detector response to protons of energies 50 to 160 MeV for use in proton spectromete

    Ocean color algorithm for remote sensing of chlorophyll

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    An algorithm for the remote detection of chlorophyll a in the ocean was tested during a Nantucket Shoals experiment conducted by NASA. A set of Multichannel Ocean Color Sensor (MOCS) data selected from one flight for each of the two altitudes flown was used to calibrate the algorithm for chlorophyll a concentration. The equations were then applied to all unsaturated MOCS data collected during the 8-day experiment to generate contour maps of chlorophyll a concentration over the shoals. One additional flight was conducted away from the shoals both on and off the Continental Shelf. Although no solar elevation or environmental corrections were made to the original conversions, the equations in these tests determined chlorophyll a concentrations to an accuracy better than 1.0 micron g/L despite the fact that the solar elevation varied between 20 deg and 56 deg during the data collection periods of the experiments

    Preliminary data for the 20 May 1974, simultaneous evaluation of remote sensors experiment

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    Several remote sensors were simultaneously used to collect data over the tidal James River from Hopewell to Norfolk, Virginia. Sensors evaluated included the Multichannel-Ocean Color Sensor, multispectral scanners, and multispectral photography. Ground truth measurements and remotely sensed data are given. Preliminary analysis indicates that suspended sediment and concentrated industrial effluent are observable from all sensors

    A review of the US Global Change Research Program and NASA's Mission to Planet Earth/Earth Observing System

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    This report reflects the results of a ten-day workshop convened at the Scripps Institution of Oceanography July 19-28, 1995. The workshop was convened as the first phase of a two part review of the U.S. Global Change Research Program (USGCRP). The workshop was organized to provide a review of the scientific foundations and progress to date in the USGCRP and an assessment of the implications of new scientific insights for future USGCRP and Mission to Planet Earth/Earth Observing System (MTPE/EOS) activities; a review of the role of NASA's MTPE/EOS program in the USGCRP observational strategy; a review of the EOS Data and Information System (EOSDIS) as a component of USGCRP data management activities; and an assessment of whether recent developments in the following areas lead to a need to readjust MTPE/EOS plans. Specific consideration was given to: proposed convergence of U.S. environmental satellite systems and programs, evolving international plans for Earth observation systems, advances in technology, and potential expansion of the role of the private sector. The present report summarizes the findings and recommendations developed by the Committee on Global Change Research on the basis of the presentations, background materials, working group deliberations, and plenary discussions of the workshop. In addition, the appendices include summaries prepared by the six working groups convened in the course of the workshop

    Nationwide randomised trial evaluating elective neck dissection for early stage oral cancer (SEND study) with meta-analysis and concurrent real-world cohort

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    BACKGROUND: Guidelines remain unclear over whether patients with early stage oral cancer without overt neck disease benefit from upfront elective neck dissection (END), particularly those with the smallest tumours. // METHODS: We conducted a randomised trial of patients with stage T1/T2 N0 disease, who had their mouth tumour resected either with or without END. Data were also collected from a concurrent cohort of patients who had their preferred surgery. Endpoints included overall survival (OS) and disease-free survival (DFS). We conducted a meta-analysis of all six randomised trials. // RESULTS: Two hundred fifty randomised and 346 observational cohort patients were studied (27 hospitals). Occult neck disease was found in 19.1% (T1) and 34.7% (T2) patients respectively. Five-year intention-to-treat hazard ratios (HR) were: OS HR = 0.71 (p = 0.18), and DFS HR = 0.66 (p = 0.04). Corresponding per-protocol results were: OS HR = 0.59 (p = 0.054), and DFS HR = 0.56 (p = 0.007). END was effective for small tumours. END patients experienced more facial/neck nerve damage; QoL was largely unaffected. The observational cohort supported the randomised findings. The meta-analysis produced HR OS 0.64 and DFS 0.54 (p < 0.001). // CONCLUSION: SEND and the cumulative evidence show that within a generalisable setting oral cancer patients who have an upfront END have a lower risk of death/recurrence, even with small tumours. // CLINICAL TRIAL REGISTRATION: NIHR UK Clinical Research Network database ID number: UKCRN 2069 (registered on 17/02/2006), ISCRTN number: 65018995, ClinicalTrials.gov Identifier: NCT00571883

    The Early Royal Society and Visual Culture

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    Recent studies have fruitfully examined the intersection between early modern science and visual culture by elucidating the functions of images in shaping and disseminating scientific knowledge. Given its rich archival sources, it is possible to extend this line of research in the case of the Royal Society to an examination of attitudes towards images as artefacts –manufactured objects worth commissioning, collecting and studying. Drawing on existing scholarship and material from the Royal Society Archives, I discuss Fellows’ interests in prints, drawings, varnishes, colorants, images made out of unusual materials, and methods of identifying the painter from a painting. Knowledge of production processes of images was important to members of the Royal Society, not only as connoisseurs and collectors, but also as those interested in a Baconian mastery of material processes, including a “history of trades”. Their antiquarian interests led to discussion of painters’ styles, and they gradually developed a visual memorial to an institution through portraits and other visual records.AH/M001938/1 (AHRC

    The Earth: Plasma Sources, Losses, and Transport Processes

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    This paper reviews the state of knowledge concerning the source of magnetospheric plasma at Earth. Source of plasma, its acceleration and transport throughout the system, its consequences on system dynamics, and its loss are all discussed. Both observational and modeling advances since the last time this subject was covered in detail (Hultqvist et al., Magnetospheric Plasma Sources and Losses, 1999) are addressed

    Granulite-facies beryllium pegmatites in the Napier Complex in Khmara and Amundsen Bays, western Enderby Land, East Antarctica

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    Four granulite-facies beryllium pegmatites of Late Archean age intrude ultrahigh-temperature Napier Complex metapelites in Khmara Bay at "Christmas Point" and "Zircon Point" and in Amundsen Bay on Mt. Pardoe. The pegmatites evolved in three major stages. During the first stage, melt from anatexis of sapphirine-bearing metapelites soon after temperatures peaked during ultrahigh-temperature metamorphism crystallized as pegmatites in inter-boudin spaces during the waning stages of associated deformation. The primary carrier of beryllium in the pegmatites at the time of their intrusion was a sapphirine-group mineral. The second stage is high-temperature metamorphism at moderate pressure, which resulted in reaction of sapphirine with quartz to form corona assemblages of sillimanite+orthopyroxene (or garnet) in the host rocks and sillimanite+garnet+ surinamite in the beryllium pegmatites. Previous investigators have attributed the corona assemblages to isobaric cooling following ultrahigh-temperature metamorphism, but the relatively large size of the coronas and their deformation in the pegmatites suggests that the coronas formed in both the host rocks and the pegmatites during a separate tectonothermal event. The third stage includes two metamorphic events at lower temperatures and moderate to low pressures when surimanite broke down to beryllian cordierite±Al-poor orthopyroxene. The presence of late-formed kyanite and andalusite in the pegmatites is consistent with decompression inferred by other investigators for these two events. Beryllium in the Late Archean pegmatites could have originated from the host granulites, which at "Christmas Point" and Mt. Pardoe have average Be contents of 3.8±2.4ppm and 3.5±1.4ppm, respectively. Beryllium content of host-rock sapphirine is 61 to 616 times whole-rock Be content, implying an important role for this mineral in supplying Be to the anatectic melt
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