Photocatalytic degradation of methyl orange using biologically enhanced tin oxide nanoparticles under UV-irradiation

Tin oxide nanoparticles (size?=?14 nm) have been prepared using DNA, a biological molecule, by co-precipitation method. The SnO₂ catalysts were characterized by X-ray diffraction, scanning electron microscope, transmission electron spectroscopy, fourier transform infra-red spectroscopy, photoluminescence spectroscopy and UV–Vis spectroscopy. The photocatalytic properties of SnO₂ nanoparticles were investigated via methyl orange as a model organic compound under UV light irradiation. The study proves SnO₂ as an efficient catalyst in removing organic pollutants in water.     

Why do they return? Beyond the economic drivers of graduate return migration

This paper explores the factors that shape the location choices of formerly mobile graduates (FMGs) initially resident in Sardinia, Italy, a less developed European region. Combining qualitative and quantitative techniques, the paper examines the reasons why some individuals decide to return after their studies, the factors that shape their decisions and how these choices unfolded in space and time. It counters the literature, which suggests that migration is a one-off linear process driven only by wealth-maximising behaviour, positing rather that access to opportunities in open meritocratic job markets and circular migration trajectories are far more salient to FMGs. This suggests that policy makers should concentrate on promoting labour market opportunities and invest in social networks that will aid brain circulation.     

The role of occupational complexity in trajectories of cognitive aging before and after retirement.

We examined the association between complexity of the main lifetime occupation and changes in cognitive ability in later life. Data on complexity of work with data, people, and things and on 4 cognitive factors (verbal, spatial, memory, and speed) were available from 462 individuals in the longitudinal Swedish Adoption/Twin Study of Aging. Mean age at the first measurement wave was 64.3 years (SD = 7.2), and 65% of the sample had participated in at least three waves of data collection. Occupational complexity with people and data were both correlated with cognitive performance. Individuals with more complex work demonstrated higher mean performance on the verbal, spatial, and speed factors. Latent growth curve analyses indicated that, after correcting for education, only complexity with people was associated with differences in cognitive performance and rate of cognitive change. Continued engagement as a result of occupational complexity with people helped to facilitate verbal function before retirement, whereas a previous high level of complexity of work with people was associated with faster decline after retirement on the spatial factor. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impact of police body armour and equipment on mobility

Body armour is used widely by law enforcement and other agencies but has received mixed reviews. This study examined the influence of stab resistant body armour (SRBA) and mandated accessories on physiological responses to, and the performance of, simulated mobility tasks. Fifty-two males (37 ± 9.2 yr, 180.7 ± 6.1 cm, 90.2 ± 11.6 kg, VO_2max 50 ± 8.5 ml kg⁻¹ min⁻¹, BMI 27.6 ± 3.1, mean ± SD) completed a running VO_2max test and task familiarisation. Two experimental sessions were completed (≥4 days in between) in a randomised counterbalanced order, one while wearing SRBA and appointments (loaded) and one without additional load (unloaded). During each session participants performed five mobility tasks: a balance task, an acceleration task that simulated exiting a vehicle, chin-ups, a grappling task, and a manoeuvrability task. A 5-min treadmill run (zero-incline at 13 km·h⁻¹, running start) was then completed. One min after the run the five mobility tasks were repeated.     

Delivery of Two‐Part Self‐Healing Chemistry via Microvascular Networks

Multiple healing cycles of a single crack in a brittle polymer coating are achieved by microvascular delivery of a two‐part, epoxy‐based self‐healing chemistry. Epoxy resin and amine‐based curing agents are transported to the crack plane through two sets of independent vascular networks embedded within a ductile polymer substrate beneath the coating. The two reactive components remain isolated and stable in the vascular networks until crack formation occurs in the coating under a mechanical load. Both healing components are wicked by capillary forces into the crack plane, where they react and effectively bond the crack faces closed. Healing efficiencies of over 60% are achieved for up to 16 intermittent healing cycles of a single crack, which represents a significant improvement over systems in which a single monomeric healing agent is delivered.     

Reactivity of supported platinum nanoclusters studied by in situ GISAXS: clusters stability under hydrogen

This paper is an initial study of the reactivity and thermal stability of atomic platinum clusters supported on Al₂O₃/SiO₂/Si(100) as a function of the thickness of the alumina film and presence of hydrogen. Extremely high thermal stability of Pt_7–10 clusters in vacuo as well as in the presence of hydrogen is observed on SiO₂/Si(100) coated with six cycles of Al₂O₃ film prepared by an atomic layer deposition technique.