993 research outputs found
Far-Infrared Hydrogen Lasers in the Peculiar Star MWC 349A
Far-infrared hydrogen recombination lines H15(alpha)(169.4 micrometers), H12(alpha)(88.8 micrometers), and H10(alpha)(52.5 micrometers) were detected in the peculiar luminous star MWC 349A from the Kuiper Airborne Observatory. Here it is shown that at least H15(alpha) is strongly amplified, with the probable amplification factor being greater than or about equal to 10(exp 3) and a brightness temperature that is greater than or about equal to 10(exp 7) kelvin. The other two lines also show signs of amplification, although to a lesser degree. Beyond H10(alpha) the amplification apparently vanishes. The newly detected amplified lines fall into the laser wavelength domain. These lasers, as well as the previously detected hydrogen masers may originate in the photoionized circumstellar disk of MWC 349A and constrain the disk's physics and structure
Open Design: Contributions, Solutions, Processes and Projects
Open design is a catchall term for various on- and offline design and making activities. It can be used to describe a type of design process that allows for (is open to) the participation of anybody (novice or professional) in the collaborative development of something. As well as this, it can mean the distribution and unrestricted use of design blueprints and documentation for the use by others. In this paper, the authors highlight various aspects of open and collaborative design and argue for the use of new terms that address what is open and when. A range of design projects and online platforms that have open attributes are then explored, whereby these terms are applied. In terms of design, the focus is specifically on the design of physical things rather than graphical, software or system design
GCIP water and energy budget synthesis (WEBS)
As part of the World Climate Research Program\u27s (WCRPs) Global Energy and Water-Cycle Experiment (GEWEX) Continental-scale International Project (GCIP), a preliminary water and energy budget synthesis (WEBS) was developed for the period 1996–1999 from the “best available” observations and models. Besides this summary paper, a companion CD-ROM with more extensive discussion, figures, tables, and raw data is available to the interested researcher from the GEWEX project office, the GAPP project office, or the first author. An updated online version of the CD-ROM is also available at http://ecpc.ucsd.edu/gcip/webs.htm/. Observations cannot adequately characterize or “close” budgets since too many fundamental processes are missing. Models that properly represent the many complicated atmospheric and near-surface interactions are also required. This preliminary synthesis therefore included a representative global general circulation model, regional climate model, and a macroscale hydrologic model as well as a global reanalysis and a regional analysis. By the qualitative agreement among the models and available observations, it did appear that we now qualitatively understand water and energy budgets of the Mississippi River Basin. However, there is still much quantitative uncertainty. In that regard, there did appear to be a clear advantage to using a regional analysis over a global analysis or a regional simulation over a global simulation to describe the Mississippi River Basin water and energy budgets. There also appeared to be some advantage to using a macroscale hydrologic model for at least the surface water budgets
AGRICULTURAL POLICY REFORM IN THE WTO: THE ROAD AHEAD
Agricultural trade barriers and producer subsidies inflict real costs, both on the countries that use these policies and on their trade partners. Trade barriers lower demand for trade partners' products, domestic subsidies can induce an oversupply of agricultural products which depresses world prices, and export subsidies create increased competition for producers in other countries. Eliminating global agricultural policy distortions would result in an annual world welfare gain of $56 billion. High protection for agricultural commodities in the form of tariffs continues to be the major factor restricting world trade. In 2000, World Trade Organization (WTO) members continued global negotiations on agricultural policy reform. To help policymakers and others realize what is at stake in the global agricultural negotiations, this report quantifies the costs of global agricultural distortions and the potential benefits of their full elimination. It also analyzes the effects on U.S. and world agriculture if only partial reform is achieved in liberalizing tariffs, tariff-rate quotas (limits on imported goods), domestic support, and export subsidies.Agricultural and Food Policy, International Relations/Trade,
Services just for men? Insights from a national study of the well men services pilots.
Men continue to have a lower life expectancy in most countries compared to women. Explanations of this gendered health inequality tend to focus on male risk taking, unhealthy lifestyle choices and resistance to seeking help from health services. In the period 2005-2008 the Scottish Government funded a nationwide community health promotion programme aimed at improving men's health, called Well Men Service Pilots (henceforth WMS)
Hubble Space Telescope NICMOS Polarization Observations of Three Edge-on Massive YSOs
Massive young stellar objects (YSOs), like low-mass YSOs, appear to be
surrounded by optically thick envelopes and/or disks and have regions, often
bipolar, that are seen in polarized scattered light at near-infrared
wavelengths. We are using the 0.2'' spatial resolution of NICMOS on Hubble
Space Telescope to examine the structure of the disks and outflow regions of
massive YSOs in star-forming regions within a few kpc of the Sun. Here we
report on 2 micron polarimetry of NGC 6334 V and S255 IRS1. NGC 6334 V consists
of a double-lobed bright reflection nebula seen against a dark region, probably
an optically thick molecular cloud. Our polarization measurements show that the
illuminating star lies ~ 2'' south of the line connecting the two lobes; we do
not detect this star at 2 micron, but there are a small radio source and a
mid-infrared source at this location. S255 IRS1 consists of two YSOs (NIRS1 and
NIRS3) with overlapping scattered light lobes and luminosities corresponding to
early B stars. Included in IRS1 is a cluster of stars from whose polarization
we determine the local magnetic field direction. Neither YSO has its scattered
light lobes aligned with this magnetic field. The line connecting the scattered
light lobes of NIRS1 is twisted symmetrically around the star; the best
explanation is that the star is part of a close binary and the outflow axis of
NIRS1 is precessing as a result of non-coplanar disk and orbit. The star NIRS3
is also offset from the line connecting its two scattered light lobes. We
suggest that all three YSOs show evidence of episodic ejection of material as
they accrete from dense, optically thick envelopes.Comment: 39 pages, 7 figures, 4 tables To be published in The Astrophysical
Journa
Maternal Gestational Immune Response and Autism Spectrum Disorder Phenotypes at 7 Years of Age in the Seychelles Child Development Study
Maternal immune markers during pregnancy and child neurodevelopmental outcomes at age 20 months in the Seychelles Child Development Study
Work-related boredom and depressed mood from a daily perspective: the moderating roles of work centrality and need satisfaction
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