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Intense molecular emission from the Lagoon nebula, M8
The discovery is reported of the second strongest source of mm and submm wavelength CO line emission, towards M8, the Lagoon Nebula in Sagittarius. The ~31 M⊙ molecular core has dimensions ~0.2 x 0.3pc and is centred on the O7V star Herschel 36 (H36), near the Hourglass Nebula in the core of M8. Emission from the CO line wings extends to the north and south of the Hourglass, although a lack of near-IR H2 emission indicates that outflow activity is much less prominent than in many active star-formation regions, and suggests that the CO line wings may trace the expanding edge of a cavity around H36. The molecular line data are compared with new near-IR narrow-band, continuum-subtracted images in He I, H2, and H,+ (Brγ) lines and archival HST emission-line images in Hα, [O III], and [S II]. The optical and near-IR data are found to be broadly consistent with previous photo-ionisation models of the Hourglass, which is excited by H 36. However, there are variations in the He I/Brγ line ratio which are difficult to explain
Far-infrared all sky diffuse mapping with AKARI
We discuss the capability of AKARI in recovering diffuse far-infrared
emission, and examine the achieved reliability. Critical issues in making
images of diffuse emission are the transient response and long-term stability
of the far-infrared detectors. Quantitative evaluation of these characteristics
are the key to achieving sensitivity comparable to or better than that for
point sources (< 20 -- 95 MJy sr-1). We describe current activity and progress
toward the production of high quality images of the diffuse far-infrared
emission using the AKARI all-sky survey data.Comment: 4 pages, 8 figures, to appear in the Proceedings of the Conference
"AKARI, a light to illuminate the misty Universe", Fukutake Hall, The
University of Tokyo, Japan, 16-19 February 200
Quantitative Soil Descriptions for Ecoregions of the United States
Researchers have defined and mapped ecological regions of the United States based on similar patterns of ecosystems such as deserts, forests, and croplands. These studies are useful in regional research, monitoring, and environmental management because data can be more readily extrapolated within the same ecoregion and to regions with similar characteristics. The description of ecoregions is largely holistic and qualitative. Conversely, quantitative information for soil are abundant and soil is an important ecosystem component related to many ecoregion properties. We used the nationwide State Soil Geographic database(STATSGO) to describe the soils of 84 Level III ecoregions in the United States. Among the 24 soil characteristics studied were texture, rock fragments, available water capacity, bulk density, and organic matter content. For each ecoregion we developed ranks to describe (i) its similarity to the U.S. average soil characteristics, (ii) the accuracy of predicting those characteristics, (iii) how well the soil map unit boundaries fit within ecoregion boundaries, (iv) the spatial relationship of soils across neighboring ecoregion boundaries, and (v) the homogeneity of texture-rock patterns. We present a national map of soil texture and rock fragments and five soil ranks for each ecoregion, and examine relationship between soils and other ecological components for selected ecoregions. Because soils relate to other ecosystem components such as vegetation, geology, and land use, the soil ranks complement and enrich the qualitative ecoregion descriptions. Similar analyses of physical or biological components of ecoregions will expand the understanding of the ecosystem patterns
CO J = 3→2 and submillimetre continuum observations of two molecular outflow sources
We present CO J=3→2 molecular line spectra, and submillimetre photometry at wavelengths λλ377 μm, 811 μm, and 1136 μm for the sources L1551 and IRC+10216. Detailed analysis of the L1551 spectra indicates the presence of strong velocity gradients in the CO emission zones, implying low optical depths and relatively high densities. The central source IRS 5 displays an infrared excess wihich cannot be explained in terms of a single temperature continuum. The emission zone is probably compact with respect to the instrumental beam size at the wavelength of peak emission (λ~50 μm), and may represent an accretion disc responsible for collimation of the high velocity gas. The far-infrared continuum of IRC+10216 has been synthesised by assuming a distribution of optically thin grains whose emissivity varies as εα λ-1, and the CO J=3→2 spectrum for this source supports earlier J=2→1 observations, implying a variable mass-loss rat
Polarization-Correlated Photon Pairs from a Single Quantum Dot
Polarization correlation in a linear basis, but not entanglement, is observed
between the biexciton and single-exciton photons emitted by a single InAs
quantum dot in a two-photon cascade. The results are well described
quantitatively by a probabilistic model that includes two decay paths for a
biexciton through a non-degenerate pair of one-exciton states, with the
polarization of the emitted photons depending on the decay path. The results
show that spin non-degeneracy due to quantum-dot asymmetry is a significant
obstacle to the realization of an entangled-photon generation device.Comment: 4 pages, 4 figures, revised discussio
Early activation of the host complement system is required to restrict central nervous system invasion and limit neuropathology during Venezuelan equine encephalitis virus infection
Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne RNA virus of the genus Alphavirus, family Togaviridae, that is responsible for sporadic outbreaks in human and equid populations in Central and South America. In order to ascertain the role that complement plays in resolving VEEV-induced disease, complement-deficient C3−/− mice were infected with a VEEV mutant (V3533) that caused mild, transient disease in immunocompetent mice. In the absence of a functional complement system, peripheral inoculation with V3533 induced much more severe encephalitis. This enhanced pathology was associated with a delay in clearance of infectious virus from the serum and more rapid invasion of the central nervous system in C3−/− mice. If V3533 was inoculated directly into the brain, however, disease outcome in C3−/− and wild-type mice was identical. These findings indicate that complement-dependent enhancement of peripheral virus clearance is critical for protecting against the development of severe VEEV-induced encephalitis
Pilot Weather Advisor System
The Pilot Weather Advisor (PWA) system is an automated satellite radio-broadcasting system that provides nearly real-time weather data to pilots of aircraft in flight anywhere in the continental United States. The system was designed to enhance safety in two distinct ways: First, the automated receipt of information would relieve the pilot of the time-consuming and distracting task of obtaining weather information via voice communication with ground stations. Second, the presentation of the information would be centered around a map format, thereby making the spatial and temporal relationships in the surrounding weather situation much easier to understan
Powers, inequalities and vulnerabilities
This research addresses the gap that is present in both missiology and family and youth ministry. Missiology does not focus on children and youth specifically, while this is the largest population in the developing world. On the other hand, family and youth ministry has a more pastoral than missional approach, not always taking cognisance of contexts like globalisation. Thus, the purpose of the book is to address the sometimes unintended and unnoticed influence of globalisation on the mission of the church, with a specific focus on children, youth and family. For this purpose, the International Association for Mission Studies study group for children, youth and families coming from different parts of the world decided to describe the powers, inequalities and vulnerabilities of children, youth and families in a globalised world from their specific contexts. Although the most prominent research methodology was critical literature studies, methods like autoethnographic, and empirical methods were also used. No decisions were made on a specific method of research for this publication. This publication can be viewed as an interdisciplinary and intra-disciplinary, because it deals with social sciences, anthropology, psychology, missiology, systematic theology and practical theology
Reviewing, indicating, and counting books for modern research evaluation systems
In this chapter, we focus on the specialists who have helped to improve the
conditions for book assessments in research evaluation exercises, with
empirically based data and insights supporting their greater integration. Our
review highlights the research carried out by four types of expert communities,
referred to as the monitors, the subject classifiers, the indexers and the
indicator constructionists. Many challenges lie ahead for scholars affiliated
with these communities, particularly the latter three. By acknowledging their
unique, yet interrelated roles, we show where the greatest potential is for
both quantitative and qualitative indicator advancements in book-inclusive
evaluation systems.Comment: Forthcoming in Glanzel, W., Moed, H.F., Schmoch U., Thelwall, M.
(2018). Springer Handbook of Science and Technology Indicators. Springer Some
corrections made in subsection 'Publisher prestige or quality
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