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How does an inclined holding beam affect discrete modulational instability and solitons in nonlinear cavities?
No full textWe study light propagation in arrays of weakly coupled
nonlinear cavities driven by an inclined holding beam.We show analytically
that both discreteness and inclination of the driving field can dramatically
change the conditions for modulational instability in discrete nonlinear
systems. We find numerically the families of resting and moving dissipative
solitons for an arbitrary inclination angle of the driving field, both in the
discrete and a quasi-continuous limits. We analyze a crossover between
resting and moving cavity solitons, and also observe novel features in the
soliton collision
'Let us have truth and liberty': contesting Britishness and otherness from the prison cell, London 1820-1826
No full textIn November 1822, London’s New
Times newspaper related the trial of a
‘wretched’, ‘shameless’ and ‘abandoned’
woman who appeared before the court of
the King’s Bench.1 Susannah Wright was
facing charges of blasphemy for the sale
of two pamphlets from the notorious Fleet
Street bookshop of imprisoned radicals
Jane and Richard Carlile. A young Nottingham
lace-worker, Susannah answered the
Carlile’s calls for volunteers to keep the
bookshop open and, assured of the support
of her ‘atheistical friends’, vowed to
‘attend to the business at all risk’.
Plasmonic solar cells
No full textThe scattering from metal nanoparticles near their localized
plasmon resonance is a promising way of increasing the light absorption in
thin-film solar cells. Enhancements in photocurrent have been observed for
a wide range of semiconductors and solar cell configurations. We review
experimental and theoretical progress that has been made in recent years,
describe the basic mechanisms at work, and provide an outlook on future
prospects in this area
Induction of HO-1 in tissue macrophages and monocytes in fatal falciparum malaria and sepsis
No full textBACKGROUND
As well as being inducible by haem, haemoxygenase -1 (HO-1) is also induced by interleukin-10 and an anti-inflammatory prostaglandin, 15d PGJ2, the carbon monoxide thus produced mediating the anti-inflammatory effects of these molecules. The cellular distribution of HO-1, by immunohistochemistry, in brain, lung and liver in fatal falciparum malaria, and in sepsis, is reported.
METHODS
Wax sections were stained, at a 1:1000 dilution of primary antibody, for HO-1 in tissues collected during paediatric autopsies in Blantyre, Malawi. These comprised 37 acutely ill comatose patients, 32 of whom were diagnosed clinically as cerebral malaria and the other 5 as bacterial diseases with coma. Another 3 died unexpectedly from an alert state. Other control tissues were from Australian adults.
RESULTS
Apart from its presence in splenic red pulp macrophages and microhaemorrhages, staining for HO-1 was confined to intravascular monocytes and certain tissue macrophages. Of the 32 clinically diagnosed cerebral malaria cases, 11 (category A) cases had negligible histological change in the brain and absence of or scanty intravascular sequestration of parasitized erythrocytes. Of these 11 cases, eight proved at autopsy to have other pathological changes as well, and none of these eight showed HO-1 staining within the brain apart from isolated moderate staining in one case. Two of the three without another pathological diagnosis showed moderate staining of scattered monocytes in brain vessels. Six of these 11 (category A) cases exhibited strong lung staining, and the Kupffer cells of nine of them were intensely stained. Of the seven (category B) cases with no histological changes in the brain, but appreciable sequestered parasitised erythrocytes present, one was without staining, and the other six showed strongly staining, rare or scattered monocytes in cerebral vessels. All six lung sections not obscured by neutrophils showed strong staining of monocytes and alveolar macrophages, and all six available liver sections showed moderate or strong staining of Kupffer cells. Of the 14 (category C) cases, in which brains showed micro-haemorrhages and intravascular mononuclear cell accumulations, plus sequestered parasitised erythrocytes, all exhibited strong monocyte HO-1 staining in cells forming accumulations and scattered singly within cerebral blood vessels. Eleven of the available and readable 13 lung sections showed strongly staining monocytes and alveolar macrophages, and one stained moderately. All of the 14 livers had strongly stained Kupffer cells. Of five cases of comatose culture-defined bacterial infection, three showed a scattering of stained monocytes in vessels within the brain parenchyma, three had stained cells in lung sections, and all five demonstrated moderately or strongly staining Kupffer cells. Brain sections from all three African controls, lung sections from two of them, and liver from one, showed no staining for HO-1, and other control lung and liver sections showed few, palely stained cells only. Australian-origin adult brains exhibited no staining, whether the patients had died from coronary artery disease or from non-infectious, non-cerebral conditions
CONCLUSIONS
Clinically diagnosed 'cerebral malaria' in children includes some cases in whom malaria is not the only diagnosis with the hindsight afforded by autopsy. In these patients there is widespread systemic inflammation, judged by HO-1 induction, at the time of death, but minimal intracerebral inflammation. In other cases with no pathological diagnosis except malaria, there is evidence of widespread inflammatory responses both in the brain and in other major organs. The relative contributions of intracerebral and systemic host inflammatory responses in the pathogenesis of coma and death in malaria deserve further investigation
Price stabilisation and microeconomic reforms in Brazil
No full textChanges in the structure of the Brazilian economy have been centred on three basic pillars: price stabilisation, fiscal reform and microeconomic reforms. The main thesis of this paper is that the reforms made the economy more resilient to external shocks, but that more changes are required especially with respect to Federal-State relations and competition policy
Self-focusing and spatial plasmon-polariton solitons
No full textWe study nonlinear propagation of surface plasmon polaritons
along an interface between metal and nonlinear Kerr dielectric. We demonstrate
numerically self-focusing of a plasmon beam at large powers and
the formation of slowly decaying spatial soliton in the presence of losses.
We develop an analytical model for describing the evolution of spatial
plasmon-solitons and observe a good agreement with numerical results
Bloch oscillations in an array of curved optical waveguides
No full textWe propose to use periodically spaced, curved optical waveguides for observation of optical Bloch
oscillations. The refractive index distribution in this system is equivalent to the sum of a periodic term
resulting from the equal spacing of the waveguides and a linear ramp, created by the curvature. We
demonstrate numerically that light propagation in this geometry exhibits spatial Bloch oscillations with
the period depending on the radius of the curvature and the wavelength
PhD by publication: a student’s perspective
No full textThis article presents the first author’s experiences as an Australian doctoral student undertaking a PhD by publication in the arena of the social sciences. She published nine articles in refereed journals and a peer-reviewed book chapter during the course of her PhD. We situate this experience in the context of current discussion about doctoral publication practices, in order to inform both postgraduate students and academics in general. The article discusses recent thinking about PhD by publication and identifies the factors that students should consider prior to adopting this approach, in terms of university requirements, supervisors’ attitudes, the research subject matter, intellectual property, capacity and working style, and issues of co-authorship. It then outlines our perceptions of the advantages and disadvantages of undertaking a PhD by publication. We suggest that, in general, the advantages outweigh the disadvantages. We conclude by reflecting on how the first author’s experiences relate to current discussions about fostering publications by doctoral students
Resonant light scattering by optical solitons
No full textWe consider the process of light scattering by optical solitons in a planar waveguide with homogeneous and inhomogeneous refractive index cores. We observe resonant reflection (Fano resonances) as well as resonant transmission of light by optical solitons. All resonant effects can be controlled in experiment by changing the soliton intensity
Nonparametric quantile estimation
No full textIn regression, the desired estimate of y|x is not always given by a conditional mean, although
this is most common. Sometimes one wants to obtain a good estimate that satisfies the property
that a proportion, t, of y|x, will be below the estimate. For t = 0.5 this is an estimate of the
median. What might be called median regression, is subsumed under the term quantile regression.
We present a nonparametric version of a quantile estimator, which can be obtained by solving a
simple quadratic programming problem and provide uniform convergence statements and bounds
on the quantile property of our estimator. Experimental results show the feasibility of the approach
and competitiveness of our method with existing ones. We discuss several types of extensions
including an approach to solve the quantile crossing problems, as well as a method to incorporate
prior qualitative knowledge such as monotonicity constraints