Spin relaxation and coherence times for electrons at the Si/SiO2 interface

While electron spins in silicon heterostructures make attractive qubits, little is known about the coherence of electrons at the Si/SiO2 interface. We report spin relaxation (T1) and coherence (T2) times for mobile electrons and natural quantum dots at a 28Si/SiO2 interface. Mobile electrons have short T1 and T2 of 0.3 us at 5 K. In line with predictions, confining electrons and cooling increases T1 to 0.8 ms at 350 mK. In contrast, T2 for quantum dots is around 10 us at 350 mK, increasing to 30 us when the dot density is reduced by a factor of two. The quantum dot T2 is shorter than T1, indicating that T2 is not controlled by T1 at 350 mK but is instead limited by an extrinsic mechanism. The evidence suggests that this extrinsic mechanism is an exchange interaction between electrons in neighboring dots.Comment: Extended with more experiments and rewritten. 6 pages, 5 figures, to be submitted to Phys. Rev.

Investigating perceptions and support for transparency and openness in research: Using card sorting in a pilot study with academic librarians

This paper explores the role of academic librarians as advocates for research transparency and open research. We describe the design and piloting of a qualitative card-sorting research protocol that investigates academic librarians' attitudes, awareness and practices related to research transparency. We report on preliminary results from interviews with librarians, presenting their conceptualizations of research transparency and open research, existing library services that support and advocate for both concepts, and potential services that would augment this support and advocacy. Library activities they feel are most important to the advancement of transparency and openness are identified and perceptions of disciplinary differences are noted

Using participatory design and visual narrative inquiry to investigate researchers’ data challenges and recommendations for library research data services

Purpose – The purpose of this paper is to report on an information gathering study on users’ research data-related challenges and proposals for library research data services (RDS). This study probes how early career researchers visually conceptualize the research process in their disciplines, their self-reported research data challenges, and their recommendations for library RDS. Design/methodology/approach – Two focus group sessions were undertaken with a total of eight early career researchers. Adopting the visual narrative inquiry method, the participants were asked to sketch the general research process in their domain. The individuals’ illustrations of the research process were then used as the basis for reflecting on their data-related needs and potential RDS that would assist them during the research process. Findings – Participants presented a research process that was more personal and, in most cases, more imperfect than the research lifecycle models that academic libraries are increasingly using for RDS development and communication. The authors present their data-related challenges, which included data access barriers, low knowledge of best practices for research data management, the need for a deeper understanding of post-publication impact, and inconsistent awareness of existing library and institution RDS. The authors outline RDS recommendations that participants proposed, which included a web-based tools, customized training sessions, and “distilled” guides to research data best practices. Practical implications – The study flagged users’ gaps in understandings of existing library and institutional RDS, suggesting that there may be an opportunity to engage users in the design of communications plans for services. The findings from this user study will inform the development of RDS at the institution. Originality/value – This paper puts forth a methodological approach that academic libraries can adapt for understanding users’ needs and user-generated design solutions

Fluorescent Silicon Clusters and Nanoparticles

The fluorescence of silicon clusters is reviewed. Atomic clusters of silicon have been at the focus of research for several decades because of the relevance of size effects for material properties, the importance of silicon in electronics and the potential applications in bio-medicine. To date numerous examples of nanostructured forms of fluorescent silicon have been reported. This article introduces the principles and underlying concepts relevant for fluorescence of nanostructured silicon such as excitation, energy relaxation, radiative and non-radiative decay pathways and surface passivation. Experimental methods for the production of silicon clusters are presented. The geometric and electronic properties are reviewed and the implications for the ability to emit fluorescence are discussed. Free and pure silicon clusters produced in molecular beams appear to have properties that are unfavourable for light emission. However, when passivated or embedded in a suitable host, they may emit fluorescence. The current available data show that both quantum confinement and localised transitions, often at the surface, are responsible for fluorescence. By building silicon clusters atom by atom, and by embedding them in shells atom by atom, new insights into the microscopic origins of fluorescence from nanoscale silicon can be expected.Comment: 5 figures, chapter in "Silicon Nanomaterials Sourcebook", editor Klaus D. Sattler, CRC Press, August 201

Monitoring Clinical Progression with Mitochondrial Disease Biomarkers

Mitochondrial disorders are genetically determined metabolic diseases due to a biochemical deficiency of the respiratory chain. Given that multi-system involvement and disease progression are common features of mitochondrial disorders they carry substantial morbidity and mortality. Despite this, no disease-modifying treatments exist with clear clinical benefits, and the current best management of mitochondrial disease is supportive. Several therapeutic strategies for mitochondrial disorders are now at a mature preclinical stage. Some are making the transition into early-phase patient trials, but the lack of validated biomarkers of disease progression presents a challenge when developing new therapies for patients. This update discusses current biomarkers of mitochondrial disease progression including metabolomics, circulating serum markers, exercise physiology, and both structural and functional imaging. We discuss the advantages and disadvantages of each approach, and consider emerging techniques with a potential role in trials of new therapies.P.F.C. is a Wellcome Trust Senior Fellow in Clinical Science (101876/Z/13/Z), and a UK NIHR Senior Investigator, who receives support from the Medical Research Council Mitochondrial Biology Unit (MC_UP_1501/2), the Wellcome Trust Centre for Mitochondrial Research (096919Z/11/Z), the Medical Research Council (UK) Centre for Translational Muscle Disease (G0601943), EU FP7 TIRCON, and the National Institute for Health Research (NIHR) Biomedical Research Centre based at Cambridge University Hospitals NHS Foundation Trust and the University of Cambridge. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. R.H. is a Wellcome Trust Investigator (109915/Z/15/Z), who receives support from the Medical Research Council (UK) (MR/N025431/1), the European Research Council (309548), the Wellcome Trust Pathfinder Scheme (201064/Z/16/Z) and the Newton Fund (UK/Turkey, MR/N027302/1). GlaxoSmithKline provides support for H.E.S. as part of their Early Talent Review Board (ETRB) Clinical Fellow program

Is it safe? Talking to teens with HIV/AIDS about death and dying: a 3-month evaluation of Family Centered Advance Care (FACE) planning ? anxiety, depression, quality of life

Purpose To determine the safety of engaging HIV-positive (HIV+) adolescents in a Family Centered Advance Care (FACE) planning intervention. Patients and methods We conducted a 2-armed, randomized controlled clinical trial in 2 hospital-based outpatient clinics from 2006?2008 with HIV+ adolescents and their surrogates (n = 76). Three 60?90 minutes sessions were conducted weekly. FACE intervention groups received: Lyon FCACP Survey©, the Respecting Choices¬ interview, and completion of The Five Wishes©. The Healthy Living Control (HLC) received: Developmental History, Healthy Tips, Future Planning (vocational, school or vocational rehabilitation). Three-month post-intervention outcomes were: completion of advance directive (Five Wishes©); psychological adjustment (Beck Depression, Anxiety Inventories); quality of life (PedsQL?); and HIV symptoms (General Health Self-Assessment). Results Adolescents had a mean age, 16 years; 40% male; 92% African-American; 68% with perinatally acquired HIV, 29% had AIDS diagnosis. FACE participants completed advance directives more than controls, using time matched comparison (P \u3c 0.001). Neither anxiety, nor depression, increased at clinically or statistically significant levels post-intervention. FACE adolescents maintained quality of life. FACE families perceived their adolescents as worsening in their school (P = 0.018) and emotional (P = 0.029) quality of life at 3 months, compared with controls. Conclusions Participating in advance care planning did not unduly distress HIV+ adolescents