3,794 research outputs found
Dwarf minke whale tourism monitoring program (2003--2008)
This report provides a comprehensive account of interactions with dwarf minke whales by swimming-with-whales (SWW) endorsed vessels in the Cairns/Cooktown Management Area of the Great Barrier Reef Marine Park over the period 2003 to 2008. Results presented in this report are primarily based on analyses of Great Barrier Reef tourism industry-collected Whale Sighting Sheets. Key management processes and outcomes, arising from bi-annual stakeholder workshops (held pre- and post-season) during the 2003–2008 Great Barrier Reef Marine Park Authority-funded Dwarf Minke Whale Tourism Monitoring Program are also summarised and discussed. During the latter three years of this program, three PhD studies (by Mangott, Sobtzick and Curnock) contributed significantly to our knowledge of this unique aggregation of dwarf minke whales, their interactions with humans in the Great Barrier Reef Marine Park and the sustainable management of these interactions. Some of the key findings of these three PhD studies are included in this report
A special simplex in the state space for entangled qudits
Focus is on two parties with Hilbert spaces of dimension d, i.e. "qudits". In
the state space of these two possibly entangled qudits an analogue to the well
known tetrahedron with the four qubit Bell states at the vertices is presented.
The simplex analogue to this magic tetrahedron includes mixed states. Each of
these states appears to each of the two parties as the maximally mixed state.
Some studies on these states are performed, and special elements of this set
are identified. A large number of them is included in the chosen simplex which
fits exactly into conditions needed for teleportation and other applications.
Its rich symmetry - related to that of a classical phase space - helps to study
entanglement, to construct witnesses and perform partial transpositions. This
simplex has been explored in details for d=3. In this paper the mathematical
background and extensions to arbitrary dimensions are analysed.Comment: 24 pages, in connection with the Workshop 'Theory and Technology in
Quantum Information, Communication, Computation and Cryptography' June 2006,
Trieste; summary and outlook added, minor changes in notatio
Defective Erythrocyte Pyruvate Kinase with Impaired Kinetics and Reduced Optimal Activity
A unique mutant form of erythrocyte pyruvate kinase has been found associated with chronic haemolytic anaemia in a child who is apparently doubly heterozygous for the mutant isoenzyme and for pyruvate kinase deficiency of the classical quantitative type. Clinical and laboratory findings conformed closely to those typically observed in homozygous pyruvate kinase deficiency anaemia. Assayed in fresh haemolysates, the isoenzyme exhibited reduced optimal activity ( c 45% of normal) and an increased Michaelis constant for phosphoenolpyruvate (four to five times greater than normal). The kinetic anomaly was only partially corrected by activation with fructose-1,6-disphosphate. Despite some common characteristics, this isoenzyme appears distinct from others reported in the literature and lends support to the polymorphous nature of heritable baemolytic anaemias secondary to defective pyruvate kinase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73844/1/j.1365-2141.1972.tb05713.x.pd
Testing T Invariance in the Interaction of Slow Neutrons with Aligned Nuclei
The study of five-fold (P even, T odd) correlation in the interaction of slow
polarized neutrons with aligned nuclei is a possible way of testing the time
reversal invariance due to the expected enhancement of T violating effects in
compound resonances. Possible nuclear targets are discussed which can be
aligned both dynamically as well as by the "brute force" method at low
temperature. A statistical estimation is performed of the five-fold correlation
for low lying p wave compound resonances of the Sb, Sb and
I nuclei. It is shown that a significant improvement can be achieved
for the bound on the intensity of the fundamental parity conserving time
violating (PCTV) interaction.Comment: 22 pages, 5 figures, published versio
Microrheology with optical tweezers: data analysis
We present a data analysis procedure that provides the solution to a long-standing issue in microrheology studies, i.e. the evaluation of the fluids' linear viscoelastic properties from the analysis of a finite set of experimental data, describing (for instance) the time-dependent mean-square displacement of suspended probe particles experiencing Brownian fluctuations. We report, for the first time in the literature, the linear viscoelastic response of an optically trapped bead suspended in a Newtonian fluid, over the entire range of experimentally accessible frequencies. The general validity of the proposed method makes it transferable to the majority of microrheology and rheology techniques
Unified analysis of terminal-time control in classical and quantum systems
Many phenomena in physics, chemistry, and biology involve seeking an optimal
control to maximize an objective for a classical or quantum system which is
open and interacting with its environment. The complexity of finding an optimal
control for maximizing an objective is strongly affected by the possible
existence of sub-optimal maxima. Within a unified framework under specified
conditions, control objectives for maximizing at a terminal time physical
observables of open classical and quantum systems are shown to be inherently
free of sub-optimal maxima. This attractive feature is of central importance
for enabling the discovery of controls in a seamless fashion in a wide range of
phenomena transcending the quantum and classical regimes.Comment: 10 page
Molecular and morphometric variation in European populations of the articulate brachiopod <i>Terebeatulina retusa</i>
Molecular and morphometric variation within and between population samples of the articulate brachiopod <i>Terebratulina</i> spp., collected in 1985-1987 from a Norwegian fjord, sea lochs and costal sites in western Scotland, the southern English Channel (Brittany) and the western Mediterranean, were measured by the analysis of variation in the lengths of mitochondrial DNA (mtDNA) fragments produced by digestion with nine restriction endonucleases and by multivariate statistical analysis of six selected morphometric parameters. Nucleotide difference within each population sample was high. Nucleotide difference between population samples from the Scottish sites, both those that are tidally contiguous and those that appear to be geographically isolated, were not significantly different from zero. Nucleotide differences between the populations samples from Norway, Brittany, Scotland and the western Mediterranean were also very low. Morphometric analysis confirmed the absence of substantial differentiation
The interview as narrative ethnography : seeking and shaping connections in qualitative research.
Acts of counter-subjectification in qualitative research are always present but are often submerged in accounts that seek to locate the power of subjectification entirely with the researcher. This is particularly so when talking to people about sensitive issues. Based on an interview-based study of infertility and reproductive disruption among British Pakistanis in Northeast England, we explore how we, as researchers, sought and were drawn into various kinds of connections with the study participants; connections that were actively and performatively constructed through time. The three of us that conducted interviews are all female academics with Ph.Ds in anthropology, but thereafter our backgrounds, life stories and experiences diverge in ways that intersected with those of our informants in complex and shifting ways. We describe how these processes shaped the production of narrative accounts and consider some of the associated analytical and ethical implications
Herbivores at the Highest Risk of Extinction Among Mammals, Birds, and Reptiles
As a result of their extensive home ranges and slow population growth rates, predators have often been perceived to suffer higher risks of extinction than other trophic groups. Our study challenges this extinction-risk paradigm by quantitatively comparing patterns of extinction risk across different trophic groups of mammals, birds, and reptiles. We found that trophic level and body size were significant factors that influenced extinction risk in all taxa. At multiple spatial and temporal scales, herbivores, especially herbivorous reptiles and large-bodied herbivores, consistently have the highest proportions of threatened species. This observed elevated extinction risk for herbivores is ecologically consequential, given the important roles that herbivores are known to play in controlling ecosystem function
Electrical Control of Plasmon Resonance with Graphene
Surface plasmon, with its unique capability to concentrate light into
sub-wavelength volume, has enabled great advances in photon science, ranging
from nano-antenna and single-molecule Raman scattering to plasmonic waveguide
and metamaterials. In many applications it is desirable to control the surface
plasmon resonance in situ with electric field. Graphene, with its unique
tunable optical properties, provides an ideal material to integrate with
nanometallic structures for realizing such control. Here we demonstrate
effective modulation of the plasmon resonance in a model system composed of
hybrid graphene-gold nanorod structure. Upon electrical gating the strong
optical transitions in graphene can be switched on and off, which leads to
significant modulation of both the resonance frequency and quality factor of
plasmon resonance in gold nanorods. Hybrid graphene-nanometallic structures, as
exemplified by this combination of graphene and gold nanorod, provide a general
and powerful way for electrical control of plasmon resonances. It holds promise
for novel active optical devices and plasmonic circuits at the deep
subwavelength scale
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