14,158 research outputs found
Marine benthic plants of Western Australia's shelf-edge atolls
One hundred and twenty-one species of marine algae, seagrasses and cyanobacteria are reported from the offshore atolls of northwestern Western Australia (the Rowley Shoals, Scott Reef and Seringapatam Reef). Included are 65 species of Rhodophyta, 40 species of Chlorophyta, nine species of Phaeophyceae, three species of Cyanophyta and four species of seagrasses. This report presents the first detailed account of marine benthic algae from these atolls. Twenty-four species are newly recorded for Western Australia, with four species (Anadyomene wrightii, Rhipilia nigrescens, Ceramium krameri and Zellera tawallina) also newly recorded for Australia
Guidance, flight mechanics and trajectory optimization. Volume 1 - Coordinate systems and time measure
Coordinate measuring system for flight control, and trajectory optimizatio
Supersymmetric Electrovacs In Gauged Supergravities
We show that the D=6 SU(2) gauged supergravity of van Nieuwenhuizen et al,
obtained by dimensional reduction of the D=7 topologically massive gauged
supergravity and previously thought not to be dimensionally reducible, can be
further reduced to five and four dimensions. On reduction to D=4 one recovers
the special case of the SU(2)XSU(2) gauged supergravity of Freedman and Schwarz
for which one of the SU(2) coupling constants vanishes. Previously known
supersymmetric electrovacs of this model then imply new ground states in 7-D.
We construct a supersymmetric electrovac solution of N=2 SU(2) gauged
supergravity in 7-D. We also investigate the domain wall solutions of these
theories and show they preserve a half of the supersymmetry.Comment: 29 pages, TeX, no figures. Introduction and conclusion rewritten. New
references added. Minor changes to all section
Staying true with the help of others: doxastic self-control through interpersonal commitment
I explore the possibility and rationality of interpersonal mechanisms of doxastic self-control, that is, ways in which individuals can make use of other people in order to get themselves to stick to their beliefs. I look, in particular, at two ways in which people can make interpersonal epistemic commitments, and thereby willingly undertake accountability to others, in order to get themselves to maintain their beliefs in the face of anticipated âepistemic temptationsâ. The first way is through the avowal of belief, and the second is through the establishment of collective belief. I argue that both of these forms of interpersonal epistemic commitment can function as effective tools for doxastic self-control, and, moreover, that the control they facilitate should not be dismissed as irrational from an epistemic perspective
âBut by blood no wolf am Iâ: Language and Agency, Instinct and Essence â Transcending Antinomies in Maggie Stiefvaterâs Shiver trilogy
Young Adult dark romance is often more questioning than its adult counterpart; different, less constraining commercial imperatives are perhaps at work, or readersâ expectations less fixed. This chapter will show how, woven into a sensitive coming-of-age narrative of first love and familial problems, Maggie Stiefvaterâs Shiver trilogy performs a far more sophisticated interrogation of the boundaries of animality and humanity than other such fictions, highlighting the centrality of language and its relationship to agency. The hero, Samâs, struggle with his lupine nature becomes an existentialist refusal to be defined by nature; other characters are tempted instead to yield to a fatalistic surrender of will. The books are tantalisingly ambivalent about the appeal of the instinctual and the borderline between an embodied humanity and the animal, particularly as manifested in the love affair of the teenage protagonists. For Marcuse, the surplus-repression of the proximity senses (smell, taste) enforces the isolation of individuals in civilisation. Stiefvater continually emphasises the sense of smell both as a trigger to sexual attraction and as an aspect of the pack sociality and sense of belonging of the wolves. Through such devices, she concretely renders the nearness of Grace and Sam (her young lovers) to wolfhood. This is contrasted with her exploration of human subjectivity through language, particularly in the perceptive depiction of silences and miscommunications and her heroâs absorption in books and poetry
Preliminary Identification of Ground-Water Nitrate Sources Using Nitrogen and Carbon Stable Isotopes, Kansas
Increasing nitrate-N in ground water is a problem in many areas with limited ground-water supplies, such as west-central Kansas. However, potential sources of nitrate-N are not known. Nitrate-N concentrations in ground water in the Hays study area in Ellis County, west-central Kansas, range from 0.9 to 26 mg/L. The δ15N signatures of the ground waters are more enriched (+16.8 to +28.7â°) than those of the soils (+8.4 to +13.7â°), strongly suggesting that nitrogen sources are not from mineralized and labile nitrogen present in the unsaturated zone. In this study, nitrate-N values greater than the U.S. EPA drinking water limit of 10 mg/L occur with δ15N values of greater than +10â°. This relationship between high nitrate-N concentrations and enriched δ15N values (greater than +10â°) in ground water has been observed in other studies in Kansas and is usually related to a human- and/or animal-waste source.
Soil cores collected near municipal wells had mean total nitrogen values of 1.2-15 mg/kg. Increased δ15N with depth in several of the cores suggests that microbial mineralization, denitrification, or volatilization processes caused the enriched δ15N signatures. Decreasing total nitrogen and nitrate-N values with depth also help support the idea of microbial processes.
Stable carbon isotopes provide supporting evidence that soils are not a major contributor to the observed nitrate-N concentration in the ground water. δ13C values of the dissolved organic carbon (DOC) in soils generally were more enriched (-11.6 to -18.8â°) while corresponding ground-water δ13C values were more depleted (-19.9 to -22.2â°), suggesting that the source of the DOC in ground water is not from the soils
Superconformal mechanics, black holes, and non-linear realizations
The OSp(2|2)-invariant planar dynamics of a D=4 superparticle near the
horizon of a large mass extreme black hole is described by an N=2
superconformal mechanics, with the SO(2) charge being the superparticle's
angular momentum. The {\it non-manifest} superconformal invariance of the
superpotential term is shown to lead to a shift in the SO(2) charge by the
value of its coefficient, which we identify as the orbital angular momentum.
The full SU(1,1|2)-invariant dynamics is found from an extension to N=4
superconformal mechanics.Comment: 19 pages, plain latex file. Slightly shortened version, two
references adde
Multiple M-wave interaction with fluxes
We present the equations of motion for multiple M0-brane (multiple M-wave or
mM0) system in general eleven dimensional supergravity background. These are
obtained in the frame of superembedding approach, but have a rigid structure:
they can be restored from SO(1,1) x SO(9) symmetry characteristic for M0. BPS
conditions for the 1/2 supersymmetric solution of these equations have the
fuzzy 2-sphere solution describing M2-brane.Comment: 4 pages, no figures, RevTeX4. V2. The discussion on BPS conditions
and some supersymmetric solutions is added. The explicit values of the
coefficients for the interacting terms are presented. Also a couple of minor
changes. V3: a small misrint corrected. Published: Phys.Rev.Lett.105 (2010)
07160
String/-brane Duality and Duality as Symmetries of Actions
We realize the string/-brane duality on the action level between the
-compactified heterotic string effective action and the -
brane effective action in dimensions by managing a Lagrange multiplier
field. A dual dictionary is composed to be available for the translation
between the elementary or solitonic solutions of the dual pair of actions. In
the same way the duality is also reconstructed on the action level as a
double dualization for the -compactified heterotic string effective
action.Comment: 9 pages, latex, no figure
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