Level spacings at the metal-insulator transition in the Anderson Hamiltonians and multifractal random matrix ensembles

We consider orthogonal, unitary, and symplectic ensembles of random matrices with (1/a)(ln x)^2 potentials, which obey spectral statistics different from the Wigner-Dyson and are argued to have multifractal eigenstates. If the coefficient $a$ is small, spectral correlations in the bulk are universally governed by a translationally invariant, one-parameter generalization of the sine kernel. We provide analytic expressions for the level spacing distribution functions of this kernel, which are hybrids of the Wigner-Dyson and Poisson distributions. By tuning the single parameter, our results can be excellently fitted to the numerical data for three symmetry classes of the three-dimensional Anderson Hamiltonians at the metal-insulator transition, previously measured by several groups using exact diagonalization.Comment: 12 pages, 8 figures, REVTeX. Additional figure and text on the level number variance, to appear in Phys.Rev.

Applying a multicentre, interdisciplinary approach to strengthen the generalisability of qualitative dementia research: the experience and challenges faced by the MinD project in Europe

Background: Generalisation of findings is an important aspect of research and essential for evidence-based practice. While generalisation is common in quantitative research, there is a lack of generalisability in qualitative research. This paper presents the experience and challenges faced by the Designing for People with Dementia (MinD) project in meeting the requirements to strengthen the generalisation of findings on the lived experience of people living with dementia and their engagement to co-create designs to empower their everyday living. Methods: Polit and Beck (2010)’s strategies to generalise qualitative findings were applied: (1) replication in sampling; (2) replication of studies; (3) meta-synthesis of findings; (4) reflexivity and conceptualization; (5) immersion with the data; and (6) thick description. Results: While it is possible to increase the generabilisabilty of qualitative evidence through the replication of the sampling to attain a large, heterogeneous sample in different and multiple contexts and environments; implementation of sound and robust research; conducting in-depth analysis and interpretation collaboratively for emergent themes; and meeting the thick description requirement, there are challenges that the project team faced in implementing some of the Polit and Beck’s strategies because of the condition, namely dementia, that our participants are having. Other challenges faced were: the language and cultural diversity in the team; diverse work and organisational procedures; and the inter-disciplinary differences relating to the methods of enquiry, approaches and techniques to conduct research. These challenges will need to be identified and addressed at the start of the project with a strong leadership to ensure a seamless journey to complete the project successfully. Trust between the researchers and participants, and time to build this trust are critical to recruitment and participation in the study; these factors are of utmost important in research involving participants with condition such as dementia

“I felt like I was missing out on something”: An evaluation of using remote technology in the classroom

As technology develops in Higher Education (HE), distance learning has adopted many different guises and supports many different needs (Keane 2013). The purpose of this study was to evaluate the use of Double Robotics on a Doctoral (level 8) postgraduate course at a HE institution. The aim of this project was to generate an understanding of student and tutor experiences more generally, while examining the feasibility and impact of Double Robotics within a doctoral programme more specifically. Data were collected through a series of focus group interviews with the student and tutors over the course of a single semester (10-weeks). The data were subject to an inductive thematic analysis (Braun and Clarke 2006, 2013). The findings of the study shed light on the interactive pitfalls of the technology and contribute to understanding the experiences of distance learners’ engagement. Four key themes were identified: quality of technology, classroom familiarity, tutor facilitation and user isolation. The significance of this study lies not only in assessing the feasibility of Double Robotics but, specifically, shedding light on the nuanced understanding tutors require to enrol and engage distance learners remotely. Most notable, the ‘isolation’ of the learner points to a heightened awareness of context that can help tutors develop robust and durable environments, which embrace both traditional classroom settings and facilitate the addition of distance learners. Building upon Tucker (2013), technological advancements in the classroom must be carefully designed to appreciate the context of the learning environment, the teacher, and the pedagogic experiences of the learners

Implementing a video-based intervention to empower staff members in an autism care organization: a qualitative study

Background Implementing good-quality health and social care requires empowerment of staff members within organizations delivering care. Video Interaction Guidance (VIG) is an intervention using positive video feedback to empower staff through reflection on practice. This qualitative study explored the implementation of VIG within an autism care organization in England, from the perspective of staff members undergoing training to deliver VIG. Methods Semi-structured interviews were conducted with a purposive sample of 7 participants working within the organization (5 staff undergoing training to deliver VIG; 2 senior managers influencing co-ordination of training). Participants were asked about their views of VIG and its implementation. The topic guide was informed by Normalization Process Theory (NPT). Data were analysed inductively and emerging issues were related to NPT. Results Five broad themes were identified: (1) participants reported that they and other staff did not understand VIG until they became involved, initially believing it would highlight negative rather than positive practice; (2) enthusiastic feedback from staff who had been involved seemed to encourage other staff to become involved; (3) key implementation challenges included demands of daily work and securing managers’ support; (4) ideas for future practice arising from empowerment through VIG seemed difficult to realise within an organizational culture reportedly unreceptive to creative ideas from staff; (5) individuals’ emotional responses to implementation seemed beyond the reach of NPT, which focused more upon collective processes. Conclusions Implementation of VIG may require recognition that it is not a ‘quick fix’. Peer advocacy may be a fruitful implementation strategy. Senior managers may need to experience VIG to develop their understanding so that they can provide appropriate implementation support. NPT may lack specificity to explain how individual agency weaves with collective processes and social systems to embed innovation in routine practice. This exploratory study has provided broad insights into facilitators and barriers to the implementation of an intervention to empower staff within an autism care organization. Further research is needed into similar interventions, including a focus upon staff members’ emotional responses and resources, and how such interventions may relate to the culture of the organization in which implementation occurs

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

A Comparison Study of Static Mapping Heuristics for a Class of Meta-tasks on Heterogeneous Computing Systems

Heterogeneous computing (HC) environments are well suited tomeet the computational demands of large, diverse groups of tasks (i.e., a meta-task). The problem of mapping (de ned as matching and scheduling) these tasks onto the machines of an HC environment has been shown, in general, to be NP-complete, requiring the development of heuristic techniques. Selecting the best heuristic to use in a given environment, however, remains a di cult problem, because comparisons are often clouded by di erent underlying assumptions in the original studies of each heuristic. Therefore, a collection of eleven heuristics from the literature has been selected, implemented, and analyzed under one set of common assumptions. The eleven heuristics examine