Rotor wake interactions with an obstacle on the ground

An investigation of the flow around an obstacle positioned within the wake of a rotor is described. A flow visualisation survey was performed using a smoke wand and particle image velocimetry, and surface pressure measurements on the obstacle were taken. The flow patterns were strongly dependent upon the rotor height above the ground and obstacle, and the relative position of the obstacle and rotor axis. High positive and suction pressures were measured on the obstacle surfaces, and these were unsteady in response to the passage of the vortex driven rotor wake over the surfaces. Integrated surface forces are of the order of the rotor thrust, and unsteady pressure information shows local unsteady loading of the same order as the mean loading. Rotor blade-tip vortex trajectories are responsible for the generation of these forces

Pretreatment prognostic value of dynamic contrast-enhanced magnetic resonance imaging vascular, texture, shape, and size parameters compared with traditional survival indicators obtained from locally advanced breast cancer patients

Objectives: The aim of this study was to determine if associations exist between pretreatment dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI)-based metrics (vascular kinetics, texture, shape, size) and survival intervals. Furthermore, the aim of this study was to compare the prognostic value of DCE-MRI parameters against traditional pretreatment survival indicators. Materials and Methods: A retrospective study was undertaken. Approval had previously been granted for the retrospective use of such data, and the need for informed consent was waived. Prognostic value of pretreatment DCE-MRI parameters and clinical data was assessed via Cox proportional hazards models. The variables retained by the final overall survival Cox proportional hazards model were utilized to stratify risk of death within 5 years. Results: One hundred twelve subjects were entered into the analysis. Regarding disease-free survival-negative estrogen receptor status, T3 or higher clinical tumor stage, large ( > 9.8 cm 3 ) MR tumor volume, higher 95th percentile ( > 79%) percentage enhancement, and reduced ( > 0.22) circularity represented the retained model variables. Similar results were noted for the overall survival with negative estrogen receptor status, T3 or higher clinical tumor stage, and large ( > 9.8 cm 3 ) MR tumor volume, again all been retained by the model in addition to higher ( > 0.71) 25th percentile area under the enhancement curve. Accuracy of risk stratification based on either traditional (59%) or DCEMRI (65%) survival indicators performed to a similar level. However, combined traditional and MR risk stratification resulted in the highest accuracy (86%). Conclusions: Multivariate survival analysis has revealed thatmodel-retained DCEMRI variables provide independent prognostic information complementing traditional survival indicators and as such could help to appropriately stratify treatment

Generalized latent class modeling using gllamm

gllamm can estimate both conventional and unconventional latent class models. Models are specified using discrete latent variables whose values determine the conditional response distributions for the classes. A new feature of gllamm is that latent class probabilities can depend on covariates. We will first discuss the conventional exploratory latent class model. When a number of fallible diagnoses of some disease are available, this model can be used to estimate the prevalence of the disease as well as the sensitivities and specificities of the tests in the absence of a gold standard. After estimating the model in gllamm, gllapred can be used to diagnose individual subjects based on their posterior class probabilities. An advantage of using gllamm is that a wide range of response types can be accommodated. To illustrate this, we consider the analysis of rankings of political goals in the study of value orientations. We will also discuss confirmatory models such as latent class factor models and apply them to attitudes to abortion data, taking the survey design into account by using probability weighting and robust standard errors. Finally, we consider latent trajectory models for investigating distinct patterns of change in longitudinal data.

Troubling Vulnerability: Designing with LGBT Young People's Ambivalence Towards Hate Crime Reporting

HCI is increasingly working with ?vulnerable? people yet there is a danger that the label of vulnerability can alienate and stigmatize the people such work aims to support. We report our study investigating the application of interaction design to increase rates of hate crime reporting amongst Lesbian, Gay, Bisexual and Transgender young people. During design-led workshops participants expressed ambivalence towards reporting. While recognizing their exposure to hate crime they simultaneously rejected ascription as victim as implied in the act of reporting. We used visual communication design to depict the young people?s ambivalent identities and contribute insights on how these fail and succeed to account for the intersectional, fluid and emergent nature of LGBT identities through the design research process. We argue that by producing ambiguous designed texts, alongside conventional qualitative data, we ?trouble? our design research narratives as a tactic to disrupt static and reductive understandings of vulnerability within HCI

Locating Ingetlingum and Suthgedling: Gilling West and Gilling East

This is an Accepted Manuscript of an article published by Taylor & Francis in Northern History on September 2009, available online: doi:10.1179/174587009X452369This article revisits the location of two ecclesiastical sites from early medieval Yorkshire, arguing that Ingetlingum was Gilling West and Suthgedling was Gilling East. It thereby clarifies the relationship between politics and geography of monastic foundation

Nielsen-Olesen strings in Supersymmetric models

We investigate the behaviour of a model with two oppositely charged scalar fields. In the Bogomol'nyi limit this may be seen as the scalar sector of N=1 supersymmetric QED, and it has been shown that cosmic strings form. We examine numerically the model out of the Bogomol'nyi limit, and show that this remains the case. We then add supersymmetry-breaking mass terms to the supersymmetric model, and show that strings still survive. Finally we consider the extension to N=2 supersymmetry with supersymmetry-breaking mass terms, and show that this leads to the formation of stable cosmic strings, unlike in the unbroken case.Comment: 7 pages, 2 figues, uses revtex4; minor typos corrected; references adde

Do historical changes in parent-child relationships explain increases in youth conduct problems?

The coincidence of historical trends in youth antisocial behavior and change in family demographics has led to speculation of a causal link, possibly mediated by declining quality of parenting and parent-child relationships. No study to date has directly assessed whether and how parenting and parent-child relationships have changed. Two national samples of English adolescents aged 16-17 years in 1986 (N = 4,524 adolescents, 7,120 parents) and 2006 (N = 716 adolescents, 734 parents) were compared using identical questionnaire assessments. Youth-reported parental monitoring, expectations, and parent-child quality time increased between 1986 and 2006. Ratings of parental interest did not change. Parenting differences between affluent and disadvantaged families narrowed over time. There was thus little evidence of a decline in quality of parenting for the population as a whole or for disadvantaged subgroups. Parent-reported youth conduct problems showed a modest increase between 1986 and 2006. Findings suggested that the increase in youth conduct problems was largely unrelated to observed change in parent-child relationships

Contamination of overt data with covert data

A research project was conducted which explored LGBT (lesbian, gay, bisexual, transgender) hate crime. Participants were invited to share their narratives and personal experiences of hate crime, discrimination and violence through semi-structured interviews. The study helped us understand how people who experience ?hate? responded to, managed and reconciled the identities for which they were victimized. This case study focuses on a situation where a research participant requested a copy of an interview they gave for the hate crime project. The interview copy was to be used for the participant?s own personal purposes. The participant?s request potentially risked the contamination of ethical (overt) data collection, with their own covert data gathering. The ethical implications of this scenario raise many questions for ethicists and researchers to discuss