799 research outputs found
Effect of feeding various antibiotics on the hemorrhagic syndrome in poultry
Call number: LD2668 .T4 1958 D45Master of Scienc
Geochemistry of volcanic rocks from the Sunda Arc
Geochemical analyses of igneous rocks can provide valuable information about processes, element fluxes, and rock lithologies not evident at the surface. This is particularly important in subduction zone settings where complex interactions between the subducting plate, mantle wedge and arc crust cannot yet be measured by alternative methods.
The Sunda arc, in SE Asia, provides an ideal opportunity to study the effects of subduction in a complex tectonic setting where the basement is poorly exposed and understood. However, in order to do so, magma compositions modified during differentiation in the arc crust must be effectively distinguished from those modified at the source. This study includes a detailed major- and trace element and isotopic (Sr-Nd-Hf-Pb) examination of volcanoes from west Java (Papandayan, Patuha and Galunggung), Central Java (Sumbing), east Java (Kelut) and Bali (Agung), the result of which provides greater insights into petrogenesis both across and along the arc.
Contamination in the arc crust is more extensive than previously recognised, particularly in west and central Java where few volcanoes can be used in order to identify subduction and source contributions. In west Java, volcanoes such as Papandayan and Patuha show significant enrichments in isotope ratios above mantle values (e.g. 87Sr/86Sr ~ 0.706, 143Nd/144Nd ~ 0.5125, 208Pb/204Pb ~ 18.91 and 176Hf/177Hf ~ 0.2827) which indicates a terrigneous crustal contaminant. At Sumbing volcano, most magma compositions are similar to those at Merapi and Merbabu, and show strong evidence for the assimilation of carbonate-rich lithologies with some magmas becoming enriched in CaO, Sr and 87Sr/86Sr.
Differentiation in volcanoes from east Java and the western part of the Lesser Sunda Islands (Bali, Lombok and Sumbawa) is dominantly controlled by fractional crystallisation, which provides better controls on source compositions. At Kelut, one group of samples show the most ‘depleted’ magma compositions yet discovered on Java, which contain MORB-like values for 143Nd/144Nd and 176Hf/177Hf (0.5130 and 0.2831 respectively). These samples represent the depleted (asthenospheric) mantle and are situated towards the front of the arc in east Java. It is likely that the progressive enrichment further back on the arc (i.e. Leucititic compositions at Ringgit-Besar) include more of an enriched (lithospheric) mantle (SCLM) component derived from the NW margin of Australia during the breakup of Gondwana
NRA: First Multiwavelength, Multiple Layer Doppler Imaging of an Active Binary
In this final report, grantee reports on data obtained from 26 orbits of continuous observing time with the Hubble Space Telescope's Goddard High Resolution Spectrograph in order to produce a comprehensive 2-D image of the RSCVn V824 Ara at MgII, CIV and for the first time ever, the coronal diagnostic line of FeXXI 1356A
The First Multiple Layer Doppler Imaging of an Active Binary
Preliminary results were presented at the Cool Stars, Stellar Systems, and the Sun in Cambridge, MA in July 1997. A copy of the two published papers (in press) is attached. The project has met or exceeded our expectations. The rapid readout data have given us an excellent data set to model in detail the flare behavior. The large number of spectral features observed between the EUVE and HST data have allowed us to compute a mean model atmosphere and compare the results to another well studied system (HR 1099 - Cycle 3 HST observation previously published). I developed a model (anisotropic macroturbulence) that fits the CIV and MgII better than previously achieved. These results have been constrained by the EUVE data. In early studies, 2 gaussians were applied to the profile. The interpretation of these features was unclear. The anisotropic macroturbulence model fits the data better than previously possible and gives a physically reasonable interpretation: there appears to be an asymmetrical distribution between the radial and tangential velocity fields. This is similar to case of the Sun
Probing surface structure on late-type stars with FRESIP
We discuss possible secondary scientific results obtainable with the FRESIP satellite in regards to surface features on solar-like stars
Airlines, Airports and Antitrust: A Proposed Strategy for Enhanced Competition
Most of this country\u27s major airports are monopolies or duopolies at which one or two dominant carriers control a high percentage of terminal facilities. Airlines have used this market power to raise fares on flights originating and terminating at such airports. Although this power has been gained in part through the process of buy-outs and mergers in the airline industry itself, it has also been gained through actions taken in concert with airport authorities, such as when agreements are entered into that effectively limit the availability of airport facilities to new entrants and other competitors. Airlines, by virtue of rights gained in their leases with airports, have achieved effective control, if not fee ownership of airport facilities. We submit that they are, therefore, subject to antitrust action under section two of the Sherman Act that makes it illegal to monopolize, or attempt to monopolize . . . any part of trade or commerce. Specifically, the airlines\u27 monopoly power over airport resources should be broken up pursuant to the essential facilities doctrine, which provides that any company controlling an essential facility or a strategic bottleneck, violates the antitrust laws if it fails to make access to that facility available to its competitor on fair and reasonable terms. Although incumbent airlines have no general duty to deal with competitors (i.e., by subleasing gates or terminal space) they are, even according to such critics of the doctrine as Judge Posner, guilty of monopolization if they refus[e] to cooperate with a competitor in circumstances where cooperation is indispensable to effective competition. \u27\u27 It has been suggested that airlines should be permitted to earn oligopoly profits as a means of solving their chronic profitability problems, thus enabling them to obtain sufficient capital for new aircraft and equipment. It is true that the airline industry today is an oligopoly, which may in fact earn oligopoly profits. Whether that airline oligopoly itself should be broken up, or whether antitrust action should be taken to break up the airline industry itself is, of course, an entirely separate question not considered in this article.\u27 What is clear, however, is that the earning of oligopoly profits through monopolization of such essential facilities as airports, is anti-competitive and results in a misallocation of resources. It is also a violation of antitrust laws
Virus taxonomy: the database of the International Committee on Taxonomy of Viruses (ICTV)
The International Committee on Taxonomy of Viruses (ICTV) is charged with the task of developing, refining, and maintaining a universal virus taxonomy. This task encompasses the classification of virus species and higher-level taxa according to the genetic and biological properties of their members; naming virus taxa; maintaining a database detailing the currently approved taxonomy; and providing the database, supporting proposals, and other virus-related information from an open-access, public web site. The ICTV web site (http://ictv.global) provides access to the current taxonomy database in online and downloadable formats, and maintains a complete history of virus taxa back to the first release in 1971. The ICTV has also published the ICTV Report on Virus Taxonomy starting in 1971. This Report provides a comprehensive description of all virus taxa covering virus structure, genome structure, biology and phylogenetics. The ninth ICTV report, published in 2012, is available as an open-access online publication from the ICTV web site. The current, 10th report (http://ictv.global/report/), is being published online, and is replacing the previous hard-copy edition with a completely open access, continuously updated publication. No other database or resource exists that provides such a comprehensive, fully annotated compendium of information on virus taxa and taxonomy
Global Neurosurgery: The Unmet Need
Globally, the lack of access to basic surgical care causes 3Â times as much deaths as HIV/AIDS, tuberculosis, and malaria combined. The magnitude of this unmet need has been described recently, and the numbers are startling. Major shifts in global health agenda have highlighted access to essential and emergency surgery as a high priority. A broad examination of the current global neurosurgical efforts to improve access has revealed some strengths, particularly in the realm of training; however, the demand grossly outstrips the supply; most people in low-income countries do not have access to basic surgical care, either due to lack of availability or affordability. Projects that help create a robust and resilient health system within low- and middle-income countries require urgent implementation. In this context, concurrent scale-up of human resources, investments in capacity building, local data collection, and analysis for accurate assessment are essential. In addition, through process of collaboration and consensus building within the neurosurgical community, a unified voice of neurosurgery is necessary to effectively advocate for all those who need neurosurgical care wherever, whenever
Aviation Law and Regulation
We sought to write a comprehensive reference book for aviation lawyers and practitioners, and airline and aircraft manufactuing executives in need of vital information regarding law and government regulation in the field of commercial and general aviation. We envision this book as an aid for the neophyte and experienced practitioner alike
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