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We employ monochromatized electron energy loss spectroscopy to study Ti3SiC2 and Ti3AlC2. By probing individual grains aligned along different axes in bulk polycrystalline Ti3SiC2 and Ti3AlC2, this approach enables determination of the anisotropy of the dielectric functions and an estimate of the free-electron lifetime in different orientations. The dielectric functions are characterized by strong interband transitions in the low energy region. The energies plasmon resonance were determined to be approximate to 5 eV and exhibit a strong orientation-dependence. Our measurements show that the free-electron lifetimes are also highly orientation-dependent. These results suggest that scattering of carriers in MAX phases is very sensitive to composition and orientation.Original Publication:G Hug, Per Eklund and A Orchowski, Orientation dependence of electron energy loss spectra and dielectric functions of Ti3SiC2 and Ti3AlC2, 2010, ULTRAMICROSCOPY, (110), 8, 1054-1058.http://dx.doi.org/10.1016/j.ultramic.2010.05.007Copyright: Elsevier Science B.V., Amsterdam.http://www.elsevier.com

Protocol for Pilot Cluster RCT of Project Respect: A school-based intervention to prevent dating and relationship violence and address health inequalities among young people

Background Dating and relationship violence (DRV) – intimate partner violence during adolescence – encompasses physical, sexual and emotional abuse. DRV is associated with a range of adverse health outcomes including injuries, sexually transmitted infections, adolescent pregnancy and mental health issues. Experiencing DRV also predicts both victimisation and perpetration of partner violence in adulthood. Prevention targeting early adolescence is important because this is when dating behaviours begin, behavioural norms become established and DRV starts to manifest. Despite high rates of DRV victimisation in England, from 22-48% among girls and 12-27% among boys ages 14-17 who report intimate relationships, no RCTs of DRV prevention programmes have taken place in the UK. Informed by two school-based interventions that have shown promising results in RCTs in the United States – Safe Dates and Shifting Boundaries – Project Respect aims to optimise and pilot a DRV prevention programme for secondary schools in England. Methods Design: Optimisation and pilot cluster RCT. Trial will include a process evaluation and assess the feasibility of conducting a phase III RCT with embedded economic evaluation. Cognitive interviewing will inform survey development. Participants: Optimisation involves four schools and pilot RCT involves six (four intervention, two control). All are secondary schools in England. Baseline surveys conducted with students in Years 8 and 9 (ages 12-14). Follow-up surveys conducted with the same cohort, 16 months post-baseline. Optimisation sessions to inform intervention and research methods will involve consultations with stakeholders, including young people. Intervention: School staff training, including guidance on reviewing school policies and addressing ‘hotspots’ for DRV and gender-based harassment; information for parents; informing students of a help-seeking app; and a classroom curriculum for students in years 9 and 10, including a student-led campaign. Primary Outcome: The primary outcome of the pilot RCT will be whether progression to a phase III RCT is justified. Testing within the pilot will also determine which of two existing scales is optimal for assessing DRV victimisation and perpetration in a phase III RCT. Discussion This will be the first RCT of an intervention to prevent DRV in the UK. If findings indicate feasibility and acceptability, we will undertake planning for a phase III RCT of effectiveness. Trial registration ISRCTN, ISRCTN 65324176. Registered 8 June 2017, https://doi.org/10.1186/ISRCTN6532417

Orientation dependence of electron energy loss spectra and dielectric functions of Ti3SiC2 and Ti3AlC2

We employ monochromatized electron energy loss spectroscopy to study Ti3SiC2 and Ti3AlC2. By probing individual grains aligned along different axes in bulk polycrystalline Ti3SiC2 and Ti3AlC2, this approach enables determination of the anisotropy of the dielectric functions and an estimate of the free-electron lifetime in different orientations. The dielectric functions are characterized by strong interband transitions in the low energy region. The energies plasmon resonance were determined to be approximate to 5 eV and exhibit a strong orientation-dependence. Our measurements show that the free-electron lifetimes are also highly orientation-dependent. These results suggest that scattering of carriers in MAX phases is very sensitive to composition and orientation.Original Publication:G Hug, Per Eklund and A Orchowski, Orientation dependence of electron energy loss spectra and dielectric functions of Ti3SiC2 and Ti3AlC2, 2010, ULTRAMICROSCOPY, (110), 8, 1054-1058.http://dx.doi.org/10.1016/j.ultramic.2010.05.007Copyright: Elsevier Science B.V., Amsterdam.http://www.elsevier.com

Electron Holography Surmounts Resolution Limit of Electron Microscopy

: In high resolution electron--off-axis holography, the complete information about amplitude and phase of the complex electron image wave is captured in a single hologram, fed to a computer, numerically reconstructed and analysed using methods of wave optical image processing. Specifically, the blurring effect due to the aberration of the objective lens of the electron microscope is corrected under reconstruction. The presented first results, achieved with a Philips CM30FEG electron microscope specially developed for the needs of high resolution electron holography, reveal that the point resolution of modern electron microscopes is significantly improved. In contrast to the light optical case, in electron microscopy the lateral resolution is not limited by the diffraction error, i.e. by the wavelength of the electrons, but instead is governed by the spherical aberration of the objective lens. As shown by Scherzer [1] already in 1936, this error can not be avoided as long as common rot..