Temperature dependent core-level photoemission study of UNiSn

UNiSn undergoes an anomalous phase transition at T-N = 47 K, at which temperature it transforms from an antiferromagnetic metal to a paramagnetic semiconductor with an energy gap similar or equal to 70 meV. In order to investigate how the electronic structure of UNiSn changes as it crosses the transition temperature, we have used the X ray photoemission spectroscopy (XPS) technique from 20 to 70 K. According to the XPS studies, the U 4f core levels are almost temperature independent while the Ni 2p core levels and the satellite structure display a weak anomaly at T-N

Effects of different culture conditions (photoautotrophic, photomixotrophic) and the auxin indole-butyric acid on the in vitro acclimatization of papaya (Carica papaya L. var. Red Maradol) plants using zeolite as support

Plant regeneration of papaya via organogenesis and somatic embryogenesis has been successful;  however, the biggest problem of in vitro culture of this species is the acclimatization of regenerated  plants, where over 70% of the plants are lost before being planted in the field. Decreasing the relative humidity inside the culture vessel and thus increasing the ventilation, appears to have a greater effect on  the adaptation of papaya plants, strengthening the function of the stomata and with this, allowing better  control of water loss from the leaves. The aim of this study was to determine the effects of different  concentrations of sucrose and indole-butyric acid (IBA) on rooting and in vitro acclimatization of plants  using sterile zeolite as support and culture vessels with increased ventilation. Three concentrations of  sucrose (0, 10 and 20 g L-1) were studied with and without auxin and as the control treatment, the  rooting culture medium with agar during 17, 27 and 37 culture days. The highest percentage of rooting  was recorded at 37 culture days in the treatment without sucrose and IBA with 80.0% and zeolite as  support. The best photosynthetic values were achieved when in vitro shoots were grown in culture  medium with auxin and different concentrations of sucrose, even though they were also high in the  treatment without the presence of IBA and without sucrose at 17 days of culture. The combined effect of the zeolite, auxin (IBA), without sucrose in the culture medium and increased ventilation allowed   photoautotrophic culture conditions which had effect of the increasing plant survival under ex vitro  acclimatization conditions.Key words: Carica papaya, photosynthesis, roots formation

Amelioration of bleomycin-induced lung fibrosis in hamsters by dietary supplementation with taurine and niacin: biochemical mechanisms.

Interstitial pulmonary fibrosis induced by intratracheal instillation of bleomycin (BL) involves an excess production of reactive oxygen species, unavailability of adequate levels of NAD and ATP to repair the injured pulmonary epithelium, and an overexuberant lung collagen reactivity followed by deposition of highly cross-linked mature collagen fibrils resistant to enzymatic degradation. In the present study, we have demonstrated that dietary supplementation with taurine and niacin offered almost complete protection against the lung fibrosis in a multidose BL hamster model. The mechanisms for the protective effect of taurine and niacin are multifaceted. These include the ability of taurine to scavenge HOCl and stabilize the biomembrane; niacin's ability to replenish the BL-induced depletion of NAD and ATP; and the combined effect of taurine and niacin to suppress all aspects of BL-induced increases in the lung collagen reactivity, a hallmark of interstitial pulmonary fibrosis. It was concluded from the data presented at this Conference that the combined treatment with taurine and niacin, which offers a multipronged approach, will have great therapeutic potential in the intervention of the development of chemically induced interstitial lung fibrosis in animals and humans

The effects of supernovae on the dynamical evolution of binary stars and star clusters

In this chapter I review the effects of supernovae explosions on the dynamical evolution of (1) binary stars and (2) star clusters. (1) Supernovae in binaries can drastically alter the orbit of the system, sometimes disrupting it entirely, and are thought to be partially responsible for `runaway' massive stars - stars in the Galaxy with large peculiar velocities. The ejection of the lower-mass secondary component of a binary occurs often in the event of the more massive primary star exploding as a supernova. The orbital properties of binaries that contain massive stars mean that the observed velocities of runaway stars (10s - 100s km s$^{-1}$) are consistent with this scenario. (2) Star formation is an inherently inefficient process, and much of the potential in young star clusters remains in the form of gas. Supernovae can in principle expel this gas, which would drastically alter the dynamics of the cluster by unbinding the stars from the potential. However, recent numerical simulations, and observational evidence that gas-free clusters are observed to be bound, suggest that the effects of supernova explosions on the dynamics of star clusters are likely to be minimal.Comment: 16 pages, to appear in the 'Handbook of Supernovae', eds. Paul Murdin and Athem Alsabti. This version replaces an earlier version that contained several typo

Rules of Engagement: Journalists’ attitudes to industry influence in health news reporting.

Health-related industries use a variety of methods to influence health news, including the formation and maintenance of direct relationships with journalists. These interactions have the potential to subvert news reporting such that it comes to serve the interests of industry in promoting their products, rather than the public interest in critical and accurate news and information. Here we report the findings of qualitative interviews conducted in Sydney, Australia, in which we examined journalists’ experiences of, and attitudes towards, their relationships with health-related industries. Participants’ belief in their ability to manage industry influence and their perceptions of what it means to be unduly influenced by industry raise important concerns relating to the psychology of influence and the realities of power relationships between industry and journalists. The analysis also indicates ways in which concerned academics and working journalists might establish more fruitful dialogue regarding the role of industry in health-related news and the extent to which increased regulation of journalist-industry relationships might be needed.NHMR

Nanoparticle–membrane interactions

Engineered nanomaterials have a wide range of applications and as a result, are increasingly present in the environment. While they offer new technological opportunities, there is also the potential for adverse impact, in particular through possible toxicity. In this review, we discuss the current state of the art in the experimental characterisation of nanoparticle-membrane interactions relevant to the prediction of toxicity arising from disruption of biological systems. One key point of discussion is the urgent need for more quantitative studies of nano-bio interactions in experimental models of lipid system that mimic in vivo membranes