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Expanded musical form
This project presents a model of expanded musical form. Arguing that musicâs expanded field is a field of experiences, rather than of discrete things, it sets out an approach to composition that centres not on the creation of aesthetic works, but on supporting an aesthetic attitude. Integrating theory and practice, this research endeavours to give definition to an attitude that apprehends music as experience. Under this attitude, the perceiver assumes no distance from the perceived as she produces the content of her musical experience in and through her dynamic bodily interactivity. This project comprises a thesis and four ephemeral performance sound installations. The thesis sets out the terms of musicâs expanded condition, drawing upon a range of disciplines â artistic, aesthetic, philosophical â to chart the pluralistic, indeterminate, open-ended structure of the expanded field. The performance sound installations explored the operations of expanded artistic practice, critiquing conceptual, ideological, and institutional terms of music and sound installation to foreground the productivity of the perceiver. In both theory and practice, this research contests the concept of âsound artâ as a distinct category. It makes the case that expanded musical form is not a break with the musical past, but its background made focal. It proposes that the presence, physicality, and place in which expanded musical form consists are musicâs always presupposed foundation
The Biology Instrument for the Viking Mars Mission
Two Viking spacecraft have successfully soft landed on the surface of Mars. Each carries, along with other scientific instruments, one biology laboratory with three different experiments designed to search for evidence of living microorganisms in material sampled from the Martian surface. This 15.5-kg biology instrument which occupies a volume of almost 28.3 dm3 is the first to carry out an in situ search for extraterrestrial life on a planet. The three experiments are called the pyrolytic release, labeled release, and gas exchange. The pyrolytic release experiment has the capability to measure the fixation of carbon dioxide or carbon monoxide into organic matter. The labeled release experiment detects metabolic processes by monitoring the production of volatile carbon compounds from a radioactively labeled nutrient mixture. The gas exchange experiment monitors the gas changes in the head space above a soil sample which is either incubated in a humid environment or supplied with a rich organic nutrient solution. Each experiment can analyze a soil sample as it is received from the surface or, as a control, analyze a soil which has been heated to above 160C. Each instrument has the capability to receive four different soils dug from the Martian surface and perform a number of analysis cycles depending on the particular experiment. This paper describes in detail the design and operation of the three experiments and the supporting subsystems
Precipitate Redistribution During Creep of Alloy 617
Nickel-based superalloys are being considered for applications within advanced nuclear power generation systems due to their high temperature strength and corrosion resistance. Alloy 617, a candidate for use in heat exchangers, derives its strength from both solid solution strengthening and the precipitation of carbide particles. However, during creep, carbides that are supposed to retard grain boundary motion are found to dissolve and re-precipitate on boundaries in tension. To quantify the redistribution, we have used electron backscatter diffraction and energy dispersive spectroscopy to analyze the microstructure of 617 after creep testing at 900 and 1000°C. The data were analyzed with respect to location of the carbides (e.g., intergranular vs. intragranular), grain boundary character, and precipitate type (i.e., Cr-rich or Mo-rich). We find that grain boundary character is the most important factor in carbide distribution; some evidence of preferential distribution to boundaries in tension is also observed at higher applied stresses. Finally, the results suggest that the observed redistribution is due to the migration of carbides to the boundaries and not the migration of boundaries to the precipitates
Magnetic Coordinate Systems
Geospace phenomena such as the aurora, plasma motion, ionospheric currents
and associated magnetic field disturbances are highly organized by Earth's main
magnetic field. This is due to the fact that the charged particles that
comprise space plasma can move almost freely along magnetic field lines, but
not across them. For this reason it is sensible to present such phenomena
relative to Earth's magnetic field. A large variety of magnetic coordinate
systems exist, designed for different purposes and regions, ranging from the
magnetopause to the ionosphere. In this paper we review the most common
magnetic coordinate systems and describe how they are defined, where they are
used, and how to convert between them. The definitions are presented based on
the spherical harmonic expansion coefficients of the International Geomagnetic
Reference Field (IGRF) and, in some of the coordinate systems, the position of
the Sun which we show how to calculate from the time and date. The most
detailed coordinate systems take the full IGRF into account and define magnetic
latitude and longitude such that they are constant along field lines. These
coordinate systems, which are useful at ionospheric altitudes, are
non-orthogonal. We show how to handle vectors and vector calculus in such
coordinates, and discuss how systematic errors may appear if this is not done
correctly
Pituitary blastoma: a pathognomonic feature of germ-line DICER1 mutations.
Individuals harboring germ-line DICER1 mutations are predisposed to a rare cancer syndrome, the DICER1 Syndrome or pleuropulmonary blastoma-familial tumor and dysplasia syndrome [online Mendelian inheritance in man (OMIM) #601200]. In addition, specific somatic mutations in the DICER1 RNase III catalytic domain have been identified in several DICER1-associated tumor types. Pituitary blastoma (PitB) was identified as a distinct entity in 2008, and is a very rare, potentially lethal early childhood tumor of the pituitary gland. Since the discovery by our team of an inherited mutation in DICER1 in a child with PitB in 2011, we have identified 12 additional PitB cases. We aimed to determine the contribution of germ-line and somatic DICER1 mutations to PitB. We hypothesized that PitB is a pathognomonic feature of a germ-line DICER1 mutation and that each PitB will harbor a second somatic mutation in DICER1. Lymphocyte or saliva DNA samples ascertained from ten infants with PitB were screened and nine were found to harbor a heterozygous germ-line DICER1 mutation. We identified additional DICER1 mutations in nine of ten tested PitB tumor samples, eight of which were confirmed to be somatic in origin. Seven of these mutations occurred within the RNase IIIb catalytic domain, a domain essential to the generation of 5p miRNAs from the 5' arm of miRNA-precursors. Germ-line DICER1 mutations are a major contributor to PitB. Second somatic DICER1 "hits" occurring within the RNase IIIb domain also appear to be critical in PitB pathogenesis
Effects of watershed land use on nitrogen concentrations and δ15 Nitrogen in groundwater
Author Posting. Š The Authors, 2005. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Biogeochemistry 77 (2006): 199-215, doi:10.1007/s10533-005-1036-2.Eutrophication is a major agent of change affecting freshwater, estuarine, and marine
systems. It is largely driven by transportation of nitrogen from natural and anthropogenic
sources. Research is needed to quantify this nitrogen delivery and to link the delivery to
specific land-derived sources. In this study we measured nitrogen concentrations and δ15N
values in seepage water entering three freshwater ponds and six estuaries on Cape Cod,
Massachusetts and assessed how they varied with different types of land use. Nitrate
concentrations and δ15N values in groundwater reflected land use in developed and pristine
watersheds. In particular, watersheds with larger populations delivered larger nitrate loads with
higher δ15N values to receiving waters. The enriched δ15N values confirmed nitrogen loading
model results identifying wastewater contributions from septic tanks as the major N source.
Furthermore, it was apparent that N coastal sources had a relatively larger impact on the N
loads and isotopic signatures than did inland N sources further upstream in the watersheds.
This finding suggests that management priorities could focus on coastal sources as a first
course of action. This would require management constraints on a much smaller population.This work was supported
by funds from the Woods Hole Oceanographic Institution Sea Grant Program, from the
Cooperative Institute for Coastal and Estuarine Environmental Technology, from
Massachusetts Department of Environmental Protection to Applied Science Associates,
Narragansett, RI, as well as from Palmer/McLeod and NOAA National Estuarine Research
Reserve Fellowships to Kevin Kroeger. This work is the result of research sponsored by NOAA
National Sea Grant College Program Office, Department of Commerce, under Grant No.
NA86RG0075, Woods Hole Oceanographic Institution Sea Grant Project No. R/M-40
The PHENIX Experiment at RHIC
The physics emphases of the PHENIX collaboration and the design and current
status of the PHENIX detector are discussed. The plan of the collaboration for
making the most effective use of the available luminosity in the first years of
RHIC operation is also presented.Comment: 5 pages, 1 figure. Further details of the PHENIX physics program
available at http://www.rhic.bnl.gov/phenix
Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV
Results are presented from a search for a W' boson using a dataset
corresponding to 5.0 inverse femtobarns of integrated luminosity collected
during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV.
The W' boson is modeled as a heavy W boson, but different scenarios for the
couplings to fermions are considered, involving both left-handed and
right-handed chiral projections of the fermions, as well as an arbitrary
mixture of the two. The search is performed in the decay channel W' to t b,
leading to a final state signature with a single lepton (e, mu), missing
transverse energy, and jets, at least one of which is tagged as a b-jet. A W'
boson that couples to fermions with the same coupling constant as the W, but to
the right-handed rather than left-handed chiral projections, is excluded for
masses below 1.85 TeV at the 95% confidence level. For the first time using LHC
data, constraints on the W' gauge coupling for a set of left- and right-handed
coupling combinations have been placed. These results represent a significant
improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe
Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV
A search for a Higgs boson decaying into two photons is described. The
analysis is performed using a dataset recorded by the CMS experiment at the LHC
from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an
integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross
section of the standard model Higgs boson decaying to two photons. The expected
exclusion limit at 95% confidence level is between 1.4 and 2.4 times the
standard model cross section in the mass range between 110 and 150 GeV. The
analysis of the data excludes, at 95% confidence level, the standard model
Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The
largest excess of events above the expected standard model background is
observed for a Higgs boson mass hypothesis of 124 GeV with a local significance
of 3.1 sigma. The global significance of observing an excess with a local
significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is
estimated to be 1.8 sigma. More data are required to ascertain the origin of
this excess.Comment: Submitted to Physics Letters
Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV
The Lambda(b) differential production cross section and the cross section
ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum
pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7
TeV using data collected by the CMS experiment at the LHC. The measurements are
based on Lambda(b) decays reconstructed in the exclusive final state J/Psi
Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and
Lambda to proton pion, using a data sample corresponding to an integrated
luminosity of 1.9 inverse femtobarns. The product of the cross section times
the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls
faster than that of b mesons. The measured value of the cross section times the
branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06
+/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for
anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are
statistical and systematic, respectively.Comment: Submitted to Physics Letters
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