Medium as message: Making an 'emancipating' film on mental health and distress

This article will be a reflective report, made by participants, facilitators and tutors on the first stage of a project entitled ‘Mentalentity’ which, had as it brief, the promotion of positive attitudes to mental health among men in rural areas. The arts ‘product’ is a 25 minute film made by a group of men in South Armagh using an action learning and action research approach.. The project is a paradigm of ‘action research’ using arts based methods also in that none of the men had ever been involved in filmmaking and had to learn a wide range of skills to convert the knowledge they were reflecting on into an arts product; avoiding the sensationalising of a very complex subject and, equally, the earnestness sometimes associated with ‘awareness raising’ projects. The project is funded by a statutory agency, the Southern Investing for Health Partnership, and is being implemented by two voluntary groups, Men Aware (South Armagh) and a pan-disability group, Out and About, working with Queen’s University, School of Education, Open Learning Programme, which facilitated and accredited the project and the Nerve Centre, an internationally renowned independent arts organisation which specialises in music, multimedia, and the moving image. The article will relate the project to a range of arts based projects undertaken by the contributors and will contextualize this work within the research in such fields as inclusive participative and emancipatory research, qualitative research methodologies, active learning pedagogy, arts based pedagogy, Social/ Relational model disability and cutting edge ‘psychosocial’ models in mental health.

Shock creation and particle acceleration driven by plasma expansion into a rarefied medium

The expansion of a dense plasma through a more rarefied ionized medium is a phenomenon of interest in various physics environments ranging from astrophysics to high energy density laser-matter laboratory experiments. Here this situation is modeled via a one-dimensional particle-in-cell simulation; a jump in the plasma density of a factor of 100 is introduced in the middle of an otherwise equally dense electron-proton plasma with an uniform proton and electron temperature of 10 eV and 1 keV, respectively. The diffusion of the dense plasma, through the rarefied one, triggers the onset of different nonlinear phenomena such as a strong ion-acoustic shock wave and a rarefaction wave. Secondary structures are detected, some of which are driven by a drift instability of the rarefaction wave. Efficient proton acceleration occurs ahead of the shock, bringing the maximum proton velocity up to 60 times the initial ion thermal speed. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3469762]

Increased endocytosis in retinal vascular endothelial cells grown in high glucose medium is modulated by inhibitors of nonenzymatic glycosylation

We sought to determine if hyperglycaemia is responsible for increased retinal vascular endothelial-cell (RVEC) endocytosis in diabetes and to assess the role of nonenzymatic glycosylation in mediation of this novel endothelial-cell pathology. RVECs were propagated in media containing either 5 or 25 mmol/l glucose for up to 10 days after which they were exposed to the protein tracer horseradish peroxidase for 30 min. The level of RVEC endocytosis was quantified in intact cell monolayers by electron microscopic stereology, and in cell lysates by a simple spectrophotometric method. The effect of the nonenzymatic glycosylation inhibitors, aminoguanidine and D-lysine, on high-glucose medium induced changes in RVEC endocytosis was tested by inclusion of these agents in the culture medium. RVECs exposed to 25 mmol/l glucose showed a stepwise increase in endocytosis of horseradish peroxidase culminating in a two- to threefold increase after 10 days. Endocytosis returned to normal levels after a further 10 days in 5 mmol/l glucose medium. The increase in RVEC endocytosis was markedly reduced, but not completely normalised, by aminoguanidine and D-lysine. Exposure of cultured RVECs to 25 mmol/l glucose causes an increase in endocytosis of similar magnitude to that experienced by RVEC in early diabetes, and implicates hyperglycaemia in the latter situation. A significant component of the increase in RVEC endocytosis appears to be mediated by nonenzymatic glycosylation.

Sperm DNA damage measured by the alkaline Comet assay as an independent predictor of male infertility and in vitro fertilization success

Objective: To evaluate sperm DNA fragmentation and semen parameters to diagnose male factor infertility and predict pregnancy after IVF.
Design: Prospective study.
Setting: Academic research laboratory.
Patient(s): Seventy-five couples undergoing IVF and 28 fertile donors.
Intervention(s): Sperm DNA fragmentation was measured by the alkaline Comet assay in semen and sperm after density gradient centrifugation (DGC). Binary logistic regression was used to analyze odds ratios (OR) and relative risks (RR) for IVF outcomes.
Main Outcome Measure(s): Semen parameters and sperm DNA fragmentation in semen and DGC sperm compared with fertilization rates, embryo quality, and pregnancy.
Result(s): Men with sperm DNA fragmentation at more than a diagnostic threshold of 25% had a high risk of infertility (OR: 117.33, 95% confidence interval [CI]: 12.72–2,731.84, RR: 8.75). Fertilization rates and embryo quality decreased as sperm DNA fragmentation increased in semen and DGC sperm. The risk of failure to achieve a pregnancy increased when sperm DNA fragmentation exceeded a prognostic threshold value of 52% for semen (OR: 76.00, CI: 8.69–1,714.44, RR: 4.75) and 42% for DGC sperm (OR: 24.18, CI: 2.89–522.34, RR: 2.16).
Conclusion(s): Sperm DNA testing by the alkaline Comet assay is useful for both diagnosis of male factor infertility and prediction of IVF outcome.

Generation of a Purely Electrostatic Collisionless Shock during the Expansion of a Dense Plasma through a Rarefied Medium

A two-dimensional numerical study of the expansion of a dense plasma through a more rarefied one is reported. The electrostatic ion-acoustic shock, which is generated during the expansion, accelerates the electrons of the rarefied plasma inducing a superthermal population which reduces electron thermal anisotropy. The Weibel instability is therefore not triggered and no self-generated magnetic fields are observed, in contrast with published theoretical results dealing with plasma expansion into vacuum. The shock front develops a filamentary structure which is interpreted as the consequence of the electrostatic ion-ion instability, consistently with published analytical models and experimental results.

Two-dimensional particle-in-cell simulation of the expansion of a plasma into a rarefied medium

The expansion of a dense plasma through a more rarefied ionized medium has been studied by means of two-dimensional particle-in-cell simulations. The initial conditions involve a density jump by a factor of 100, located in the middle of an otherwise equally dense electron-proton plasma with uniform proton and electron temperatures of 10 eV and 1 keV, respectively. Simulations show the creation of a purely electrostatic collisionless shock together with an ion-acoustic soliton tied to its downstream region. The shock front is seen to evolve in filamentary structures consistently with the onset of the ion-ion instability. Meanwhile, an un-magnetized drift instability is triggered in the core part of the dense plasma. Such results explain recent experimental laser-plasma experiments, carried out in similar conditions, and are of intrinsic relevance to non-relativistic shock scenarios in the solar and astrophysical systems.

Massive stars exploding in a He-rich circumstellar medium - III. SN 2006jc: infrared echoes from new and old dust in the progenitor CSM

We present near- (NIR) and mid-infrared (MIR) photometric data of the Type Ibn supernova (SN) 2006jc obtained with the United Kingdom Infrared Telescope (UKIRT), the Gemini North Telescope and the Spitzer Space Telescope between days 86 and 493 post-explosion. We find that the IR behaviour of SN 2006jc can be explained as a combination of IR echoes from two manifestations of circumstellar material. The bulk of the NIR emission arises from an IR echo from newly condensed dust in a cool dense shell (CDs) produced by the interaction of the ejecta Outward shock with a dense shell of circumstellar material ejected by the progenitor in a luminous blue variable (LBV)-like outburst about two years prior to the SN explosion. The CDs dust mass reaches a modest 3.0 x 10(-4) M-circle dot by day 230. While dust condensation within a CDs formed behind the ejecta inward shock has been proposed before for one event (SN 1998S), SN 2006jc is the first one showing evidence for dust condensation in a CDs formed behind the ejecta outward shock in the circumstellar material. At later epochs, a substantial and growing contribution to the IR fluxes arises from an IR echo from pre-existing dust in the progenitor wind. The mass of the pre-existing circumstellar medium (CSM) dust is at least similar to 8 x 10(-3) M-circle dot. This paper therefore adds to the evidence that mass-loss from the progenitors of core-collapse SNe could be a major source of dust in the Universe. However, yet again, we see no direct evidence that the explosion of an SN produces anything other than a very modest amount of dust.

Divergence of chemical function in the alkaline phosphatase superfamily: Structure and mechanism of the P-C bond cleaving enzyme phosphonoacetate hydrolase

Phosphonates constitute a class of natural products that mimic the properties of the more common organophosphate ester metabolite yet are not readily degraded owing to the direct linkage of the phosphorus atom to the carbon atom. Phosphonate hydrolases have evolved to allow bacteria to utilize environmental phosphonates as a source of carbon and phosphorus. The work reported in this paper examines one such enzyme, phosphonoacetate hydrolase. By using a bioinformatic approach, we circumscribed the biological range of phosphonoacetate hydrolase to a select group of bacterial species from different classes of Proteobacteria. In addition, using gene context, we identified a novel 2-aminoethylphosphonate degradation pathway in which phosphonoacetate hydrolase is a participant. The X-ray structure of phosphonoformate-bound phosphonoacetate hydrolase was determined to reveal that this enzyme is most closely related to nucleotide pyrophosphatase/diesterase, a promiscuous two-zinc ion metalloenzyme of the alkaline phosphatase enzyme superfamily. The X-ray structure and metal ion specificity tests showed that phosphonoacetate hydrolase is also a two-zinc ion metalloenzyme. By using site-directed mutagenesis and P-32-labeling strategies, the catalytic nucleophile was shown to be Thr64. A structure-guided, site-directed mutation-based inquiry of the catalytic contributions of active site residues identified Lys126 and Lys128 as the most likely candidates for stabilization of the aci-carboxylate dianion leaving group. A catalytic mechanism is proposed which combines Lys12/Lys128 leaving group stabilization with zinc ion activation of the Thr64 nucleophile and the substrate phosphoryl group.

THE INTERSTELLAR-MEDIUM

The interstellar medium is the tenuous gas that fills the space between the stars of our Galaxy. Though insignificant optically, its variety and richness are revealed in observations at other wavelengths. From relatively dense clouds of gas new stars are formed. The deme clouds show, through infrared and millimetre wave measurements, a complex chemistry. We describe in particular how an understanding of the chemistry brings with it information about the nature of the clouds and how they are evolving. We show how the techniques that have been developed for interstellar clouds may also be applied to circumstellar environments and to ejecta from transient dramatic events such as novae and supernovae.