Monte-Carlo dosimetry on a realistic cell monolayer geometry exposed to alpha particles

The energy and specific energy absorbed in the main cell compartments (nucleus and cytoplasm) in typical radiobiology experiments are usually estimated by calculations as they are not accessible for a direct measurement. In most of the work, the cell geometry is modelled using the combination of simple mathematical volumes. We propose a method based on high resolution confocal imaging and ion beam analysis (IBA) in order to import realistic cell nuclei geometries in Monte-Carlo simulations and thus take into account the variety of different geometries encountered in a typical cell population. Seventy-six cell nuclei have been imaged using confocal microscopy and their chemical composition has been measured using IBA. A cellular phantom was created from these data using the ImageJ image analysis software and imported in the Geant4 Monte-Carlo simulation toolkit. Total energy and specific energy distributions in the 76 cell nuclei have been calculated for two types of irradiation protocols: a 3 MeV alpha particle microbeam used for targeted irradiation and a 239Pu alpha source used for large angle random irradiation. Qualitative images of the energy deposited along the particle tracks have been produced and show good agreement with images of DNA double strand break signalling proteins obtained experimentally. The methodology presented in this paper provides microdosimetric quantities calculated from realistic cellular volumes. It is based on open-source oriented software that is publicly available

Relationship Contexts as Sources of Socialization: An Exploration of Intimate Partner Violence Experiences of Economically Disadvantaged African American Adolescents

Intimate partner violence (IPV) among African Americans is a serious public health concern. Research suggest that African Americans adolescents, particularly those from economically disadvantaged communities, are at heightened risk for experiencing and perpetrating dating violence compared to youth from other racial and ethnic groups. In the present study, we examined different relationship contexts that are sources of IPV socialization. Semi-structured interviews were conducted with 22 economically disadvantaged African American adolescents. Content analysis yielded five relationship contexts through which the participants witnessed, experienced, and perpetrated IPV: (a) adolescents’ own dating relationships (64%), (b) siblings and extended family members (e.g., cousins, aunts, uncles) (59%), (c) parent-partners (27%), (d) friends (23%), and (e) neighbors (18%). Adolescents also frequently described IPV in their own dating relationships and in parent-partner relationships as mutual. Moreover, they appeared to minimize the experience of IPV in their own relationships. Efforts to reduce rates of IPV among economically disadvantaged African American adolescents should consider these relational contexts through which adolescents are socialized with regards to IPV and adolescents’ beliefs about mutual violence in relationships. Results highlight the importance of culturally relevant prevention and intervention programs that consider these relationship contexts

The Relationship Between Parenting and Delinquency: A Meta-analysis

This meta-analysis of 161 published and unpublished manuscripts was conducted to determine whether the association between parenting and delinquency exists and what the magnitude of this linkage is. The strongest links were found for parental monitoring, psychological control, and negative aspects of support such as rejection and hostility, accounting for up to 11% of the variance in delinquency. Several effect sizes were moderated by parent and child gender, child age, informant on parenting, and delinquency type, indicating that some parenting behaviors are more important for particular contexts or subsamples. Although both dimensions of warmth and support seem to be important, surprisingly very few studies focused on parenting styles. Furthermore, fewer than 20% of the studies focused on parenting behavior of fathers, despite the fact that the effect of poor support by fathers was larger than poor maternal support, particularly for sons. Implications for theory and parenting are discussed

Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

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

The shifting discourses of educational leadership:International trends and Scotland’s response

Increasing emphasis has been placed on leadership within educational theory, policy and practice. Drawing on a wide range of academic literature and policy documents, this paper explores how the discourse of leadership has shifted and for what purposes. The authors are critical of the lack of conceptual underpinning for that discourse, evident both nationally and internationally, and they identify key issues that the teaching profession has been left to try to understand and make sense of. They caution that, despite attempts to align contemporary policy developments to position leadership as inherent in the role of every teacher, flaws in the conceptualisation of leadership, and particularly in favoured forms such as ‘distributed leadership’ and ‘teacher leadership’, pose significant challenges to a serious attempt to ‘reprofessionalise’ teachers. Contemporary developments in Scottish education are referred to, exemplifying key tensions inherent in translating international trends into practice