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Mental health first aid training in a workplace setting: a randomized controlled trial [ISRCTN 13249129]
No full textBACKGROUND
The Mental Health First Aid training course was favorably evaluated in an uncontrolled trial in 2002 showing improvements in participants' mental health literacy, including knowledge, stigmatizing attitudes, confidence and help provided to others. This article reports the first randomized controlled trial of this course.
METHODS
Data are reported on 301 participants randomized to either participate immediately in a course or to be wait-listed for 5 months before undertaking the training. The participants were employees in two large government departments in Canberra, Australia, where the courses were conducted during participants' work time. Data were analyzed according to an intention-to-treat approach.
RESULTS
The trial found a number of benefits from this training course, including greater confidence in providing help to others, greater likelihood of advising people to seek professional help, improved concordance with health professionals about treatments, and decreased stigmatizing attitudes. An additional unexpected but exciting finding was an improvement in the mental health of the participants themselves.
CONCLUSIONS
The Mental Health First Aid training has shown itself to be not only an effective way to improve participants' mental health literacy but also to improve their own mental health. It is a course that has high applicability across the community
A quantum chemical approach to the design of chiral negative index materials
No full textThis paper presents methodology developed for the computational modeling and design of negative refractive index materials (NIMs) based on molecular chirality. An application of the methodology is illustrated by ab initio computations on two organometallic molecules which constitute the monomer units of a chiral polymer. Comparisons with experimental data for the polymer are made. Even though the resulting chirality parameter for the pristine material is small, it is shown that negative index can be achieved by introducing sharp plasmonic resonances with metal nanoparticle inclusions
Optical bullets and "rockets" in nonlinear dissipative systems and their transformations and interactions
No full textWe demonstrate the existence of stable optical light bullets in
nonlinear dissipative media for both cases of normal and anomalous
chromatic dispersion. The prediction is based on direct numerical
simulations of the (3+1)-dimensional complex cubic-quintic Ginzburg-Landau equation. We do not impose conditions of spherical or cylindrical
symmetry. Regions of existence of stable bullets are determined in the
parameter space. Beyond the domain of parameters where stable bullets are
found, unstable bullets can be transformed into “rockets” i.e. bullets
elongated in the temporal domain. A few examples of the interaction
between two optical bullets are considered using spatial and temporal interaction planes
Sampled Bragg gratings in chalcogenide (As2S3) rib-waveguides
No full textWe have written a sampled Bragg grating into a highly
photosensitive chalcogenide (As2S3) rib-waveguide using a scanning Sagnac
interferometer. The grating exhibits evenly spaced rejection peaks over a 40
nm bandwidth. We estimate the induced refractive index change of the
waveguide to be over 0.03 by matching the measured spectrum to numerical
solutions of the coupled mode equations while accounting for an induced
chirp. The sampled Bragg grating presented is comparable in strength and
bandwidth to the best sampled Bragg gratings obtained to date in silica
optical fibre
Atom-atom interactions at and between metal surfaces at nonzero temperature
No full textWe have investigated the temperature-dependent Casimir-Polder interaction between two oscillators in the proximity of metal surfaces. The interaction near a single metal surface has much in common with the interaction in free space. However, at any finite temperature the long-range asymptote is equal to the high-temperature asymptote. This asymptote, which originates not from the n=0 term in the Matsubara summation but from thermal population of the n>0 terms, is F(R)=-2kBTα02/R6. This should be compared with the more rapidly decaying zero-temperature Casimir-Polder asymptote, F(R)≈-13ħcα02/(2πR7). The interaction in the midplane between two metallic surfaces is very different. The nonretarded interaction decreases exponentially and the interaction is dominated by an enhanced Casimir-Polder-like asymptote. At large separations this asymptote also decays exponentially. For any relevant temperatures the long-range asymptote is no longer equal to the high-temperature limit. In other words crossover to a classical limit found for the long-range interaction in free space, and on a metal surface, is not always valid in a narrow cavity
Delay of squeezing and entanglement using electromagnetically induced transparency in a vapour cell
No full textWe demonstrate experimentally the delay of squeezed light
and entanglement using Electromagnetically Induced Transparency (EIT)
in a rubidium vapour cell. We perform quadrature amplitude measurements
of the probe field and find no appreciable excess noise from the EIT
process. From input squeezing of 3.2±0.5 dB at low sideband frequencies,
we observed the survival of 2.0±0.5 dB of squeezing at the EIT output.
By splitting the squeezed light on a beam-splitter, we generated biased
entanglement between two beams. We transmit one of the entangled beams
through the EIT cell and correlate the quantum statistics of this beam with
its entangled counterpart. We experimentally observed a 2.2±0.5μs delay
of the biased entanglement and obtained a preserved degree of wavefunction
inseparability of 0.71±0.01, below the unity value for separable states
Entanglement screening by nonlinear resonances
No full textWe show that nonlinear resonances in a classically mixed phase space allow us to define generic, strongly entangled multipartite quantum states. The robustness of their multipartite entanglement increases with the particle number, i.e., in the semiclassical limit, for those classes of diffusive noise which assist the quantum-classical transition
Lee-Carter mortality forecasting: a multi-country comparison of variants and extensions
No full textWe compare the short- to medium-term accuracy of five variants or extensions of the Lee-Carter method for mortality forecasting. These include the original Lee-Carter, the Lee-Miller and Booth-Maindonald-Smith variants, and the more flexible Hyndman-Ullah and De Jong-Tickle extensions. These methods are compared by applying them to sex-specific populations of 10 developed countries using data for 1986-2000 for evaluation. All variants and extensions are more accurate than the original Lee-Carter method for forecasting log death rates, by up to 61%. However, accuracy in log death rates does not necessarily translate into accuracy in life expectancy. There are no significant differences among the five methods in forecast accuracy for life expectancy
Economic crisis, Henryk Grossman and the responsibility of socialists
No full textHenryk Grossman’s discussion of economic crises was designed to
complement his Leninist understanding of politics. For Grossman, as for
Marx, the fundamental contradiction of capitalist production is between the
unlimited scope for expanding the output of use values and restrictions
imposed by the framework of producing profits. The increasing weight of
capitalists’ outlays on dead compared to living labour, which is the only
source of new value, gives rise to the system’s tendency to break down and
hence to economic crises. Deep financial crises can only be understood in
the context of developments in production and particularly movements in the
rate of profit. The initial widespread hostility to Grossman’s development of
Marxist economics can mainly be explained in terms of the logics of social
democratic and Stalinist politics. In contrast to dominant views on the left
today, the Marxist tradition in which Grossman stood places the construction
of organisations capable of assisting the working class’s conquest of
political power at the heart of the responsibility of socialists. Grossman’s
political practice expressed his understanding of the close relationship
between capitalism’s breakdown tendency and the importance of building a
revolutionary party
The Black Label: trade mark dilution, culture jamming, and the no logo movement
No full textThis article considers the ongoing debate over the appropriation of well-known and
famous trade marks by the No Logo Movement for the purposes of political and social
critique. It focuses upon one sensational piece of litigation in South Africa, Laugh It
Off Promotions v. South African Breweries International (Finance) B.V. t/a Sabmark
International. In this case, a group called Laugh It Off Promotions subjected the
trade marks of the manufacturers of Carling Beer were subjected to parody, social
satire, and culture jamming. The beer slogan “Black Label” was turned into a T-Shirt
entitled “Black Labour/ White Guilt”. In the ensuing litigation, the High Court of
South Africa and the Supreme Court of Appeal were of the opinion that the
appropriation of the mark was a case of hate speech. However, the Constitutional
Court of South Africa disagreed, finding that the parodies of a well-known, famous
trade mark did not constitute trade mark dilution. Moseneke J observed that there was
a lack of evidence of economic or material harm; and Sachs J held that there is a
need to provide latitude for parody, laughter, and freedom of expression. The decision
of the Constitutional Court of South Africa provides some important insights into the
nature of trade mark dilution, the role of parody and satire, and the relevance of
constitutional protections of freedom of speech and freedom of expression. Arguably,
the ruling will be of help in the reformation of trade mark dilution law in other
jurisdictions – such as the United States. The decision in Laugh It Off Promotions v.
South African Breweries International demonstrates that trade mark law should not
be immune from careful constitutional scrutiny