Absolute Transition Probabilities of Lines in the Spectra of Astrophysical Atoms, Molecules, and Ions

Progress in the investigation of absolute transition probabilities (A-values or F values) for ultraviolet lines is reported. A radio frequency ion trap was used for measurement of transition probabilities for intersystem lines seen in astronomical spectra. The intersystem line at 2670 A in Al II, which is seen in pre-main sequence stars and symbiotic stars, was studied

Reconceptualising academic development as community development: lessons from working with Syrian academics in exile

This paper focuses on academic development for Syrian academics in exile. Academic development first emerged in resource-rich, global North environments including the UK, the USA, Australia, and Scandinavia nearly 50 years ago as reported by Gosling (International Journal for Academic Development, 14(1):5–18, 2009), and the majority of research studies in this field focus on activities in global North, resource-rich, institutional settings. Yet academics in resource-poor, [post-] conflict and post-colonial contexts face different challenges and circumstances, and have different academic development needs. This paper extends the conceptual and contextual scope of this field by investigating the experiences and academic development needs of Syrian academics in exile, and interrogating the concept of academic development within that context. It establishes the background context of Syrian academia in exile, before summarising the nature and aims of the Council for At Risk Academics (Cara) Syria Programme. It then outlines the study’s methodology, before presenting the findings of a thematic analysis of a multi-level data set. It then interrogates the concept and normative terrain of academic development in light of these findings, and proposes a model for academic community development to support academic communities in exile, and marginalised academic communities more widely

Absolute absorption cross sections of ozone at 300 K, 228 K and 195 K in the wavelength region 185-240 nm

An account is given of progress of work on absorption cross section measurements of ozone at 300 K, 228 K and 195 K in the wavelength region 185-240 nm. In this wavelength region, the penetration of solar radiation into the Earth's atmosphere is controlled by O2 and O3. The transmitted radiation is available to dissociate trace species such as halocarbons and nitrous oxide. We have recently measured absolute absorption cross sections of O3 in the wavelength region 240-350 nm (Freeman et al., 1985; Yoshino et al., 1988). We apply these proven techniques to the determination of the absorption cross section of O3 at 300 K, 228 K and 195 K throughout the wavelength region 185-240 nm. A paper titled 'Absolute Absorption Cross Section Measurements of Ozone in the Wavelength Region 185-254 nm and the Temperature Dependence' has been submitted for publication in the Journal of Geophysical Research

Determination of spectroscopic properties of atmospheric molecules from high resolution vacuum ultraviolet cross section and wavelength measurements

Progress is given on work on: cross section measurements in the transmission window regions of the Schumann-Runge bands of oxygen; the determinations of predissociation linewidths; the theoretical calculation of band oscillator strengths of the Schumann-Runge absorption bands of O-16O-18; the determination of molecular spectroscopic constants; and the combined Herzberg continuum cross sections. The experimental investigations relevant to the cross section measurements, predissociation linewidths, and molecular spectroscopic constants are effected at high resolution with a 6.65 m scanning spectrometer which is, by virtue of its small instrumental width (FWHM = 0.0013 nm), suitable for cross section measurements of molecular bands with discrete rotational structure. Such measurements are needed for accurate calculations of the stratospheric production of atomic oxygen and heavy ozone formed following the photo-predissociation of O-16O-18 by solar radiation penetrating between the absorption lines of O-16(sub 2)

Visual perspective and the characteristics of mind wandering

Peer reviewedPublisher PD

When Imagining Yourself in Pain, Visual Perspective Matters : The Neural and Behavioral Correlates of Simulated Sensory Experiences

© 2015 Massachusetts Institute of TechnologyPeer reviewedPublisher PD

New directions in EEG measurement: an investigation into the fidelity of electrical potential sensor signals

Low frequency noise performance is the key indicator in determining the signal to noise ratio of a capacitively coupled sensor when used to acquire electroencephalogram signals. For this reason, a prototype Electric Potential Sensor device based on an auto-zero operational amplifier has been developed and evaluated. The absence of 1/f noise in these devices makes them ideal for use with signal frequencies ~10 Hz or less. The active electrodes are designed to be physically and electrically robust and chemically and biochemically inert. They are electrically insulated (anodized) and have diameters of 12 mm or 18 mm. In both cases, the sensors are housed in inert stainless steel machined housings with the electronics fabricated in surface mount components on a printed circuit board compatible with epoxy potting compounds. Potted sensors are designed to be immersed in alcohol for sterilization purposes. A comparative study was conducted with a commercial wet gel electrode system. These studies comprised measurements of both free running electroencephalogram and Event Related Potentials. Quality of the recorded electroencephalogram was assessed using three methods of inspection of raw signal, comparing signal to noise ratios, and Event Related Potentials noise analysis. A strictly comparable signal to noise ratio was observed and the overall conclusion from these comparative studies is that the noise performance of the new sensor is appropriate