Magnetotransport Properties of Quasi-Free Standing Epitaxial Graphene Bilayer on SiC: Evidence for Bernal Stacking

We investigate the magnetotransport properties of quasi-free standing epitaxial graphene bilayer on SiC, grown by atmospheric pressure graphitization in Ar, followed by H$_2$ intercalation. At the charge neutrality point the longitudinal resistance shows an insulating behavior, which follows a temperature dependence consistent with variable range hopping transport in a gapped state. In a perpendicular magnetic field, we observe quantum Hall states (QHSs) both at filling factors ($\nu$) multiple of four ($\nu=4, 8, 12$), as well as broken valley symmetry QHSs at $\nu=0$ and $\nu=6$. These results unambiguously show that the quasi-free standing graphene bilayer grown on the Si-face of SiC exhibits Bernal stacking.Comment: 12 pages, 5 figure

Nonequilibrium fluctuation induced escape from a metastable state

Based on a simple microscopic model where the bath is in a non-equilibrium state we study the escape from a metastable state in the over-damped limit. Making use of Fokker-Planck-Smoluchowski description we derive the time dependent escape rate in the non-stationary regime in closed analytical form which brings on to fore a strong non-exponential kinetic of the system mode.Comment: 4 pages, no figures, EPJ class file include

Low-energy excitations of a boson pair in a double-well trap

The states of a boson pair in a one-dimensional double-well potential are investigated. Properties of the ground and lowest excited states of this system are studied, including the two-particle wavefunction, momentum pair distribution and entanglement. The effects of varying both the barrier height and the effective interaction strength are investigated.Comment: 16 pages, 15 figure

Remarks on the KLS conjecture and Hardy-type inequalities

We generalize the classical Hardy and Faber-Krahn inequalities to arbitrary functions on a convex body $\Omega \subset \mathbb{R}^n$, not necessarily vanishing on the boundary $\partial \Omega$. This reduces the study of the Neumann Poincar\'e constant on $\Omega$ to that of the cone and Lebesgue measures on $\partial \Omega$; these may be bounded via the curvature of $\partial \Omega$. A second reduction is obtained to the class of harmonic functions on $\Omega$. We also study the relation between the Poincar\'e constant of a log-concave measure $\mu$ and its associated K. Ball body $K_\mu$. In particular, we obtain a simple proof of a conjecture of Kannan--Lov\'asz--Simonovits for unit-balls of $\ell^n_p$, originally due to Sodin and Lata{\l}a--Wojtaszczyk.Comment: 18 pages. Numbering of propositions, theorems, etc.. as appeared in final form in GAFA seminar note

Quantum Chessboards in the Deuterium Molecular Ion

We present a new algorithm for vibrational control in deuterium molecules that is feasible with current experimental technology. A pump mechanism is used to create a coherent superposition of the D2+ vibrations. A short, intense infrared control pulse is applied after a chosen delay time to create selective interferences. A `chessboard' pattern of states can be realized in which a set of even- or odd-numbered vibrational states can be selectively annihilated or enhanced. A technique is proposed for experimental realization and observation of this effect using 5 fs pulses of 790 nm radiation, with intermediate intensity (5e13 W/cm2)Comment: 12 pages, 5 figure

Mapping the current psychology provision for children and young people with juvenile dermatomyositis

Objectives: Juvenile Dermatomyositis (JDM) is a rare, chronic autoimmune condition of childhood, with known psychosocial implications. In this study, we sought to establish current psychological support for children and young people across the UK with rheumatic conditions, with a specific focus on those with JDM. Methods: Electronic surveys were distributed to the 15 centres that belong to the JDM Research Group in the UK, collecting responses from health-care professionals in the fields of medicine, nursing and psychology. Results: One hundred per cent of professionals from medicine and nursing replied from all 15 centres. Of these, 7 (47%) did not have a named psychologist as part of their rheumatology team, despite the majority [13 (87%)] having >200 paediatric rheumatology patients. Of the remaining centres, hospital psychology provision varied considerably. When rating their service, only 3 (8%) of 40 professionals scored their service as five (where one is poor and five is excellent); there were wide discrepancies in these scores. Many challenges were discussed, including limited psychology provision, lack of time and difficulties in offering support across large geographical areas. Conclusion: Many of the challenges discussed are applicable to other centres worldwide. Suggestions have been proposed that might help to improve the situation for children and young people with rheumatic conditions, including JDM. Based on these findings, we suggest that rheumatology teams maximize use of these data to advocate and work toward more comprehensive psychology provision and support in their individual centres

The Influence of Lumbopelvic Function on Perceived Ankle Function in Individuals with Chronic Ankle Instability

Perceived functional impairments measured via patient-reported outcomes (PROs) are associated with reduced postural control ability in CAI patients. Furthermore, hip and trunk neuromuscular impairments are critical factors that can cause decreased postural stability in those with CAI. Identifying the relevance between reduced lumbopelvic function and impaired sensory-perceptual outcomes might direct clinicians to novel methods for CAI patients to improve postural control ability and perceived ankle function. Therefore, the aim of this study was to examine the relationship between tests of lumbopelvic function and PROs in individuals with CAI. Thirty-three individuals with CAI underwent assessment of transversus abdominis and lumbar multifidus muscle contractility using diagnostic ultrasound; lumbopelvic stability via the unilateral hip bridge, trunk flexion endurance, Biering-Sorensen, and side plank tests; and isometric hip extension, abduction, and external rotation strength via hand-held dynamometry. We assessed PROs including the Foot and Ankle Ability Measure (FAAM-ADL and FAAM-Sport), the Tampa Scale of Kinesiophobia-11 and Fear-Avoidance Beliefs Questionnaire, and the Self-Efficacy of Balance Scale. Pearson product moment correlations and Separate backward linear regression analyses were used to identify the relationship between lumbopelvic function and PROs’ scores. Alpha was set a priori at P2=0.20, P2=0.29, Phttps://digitalcommons.odu.edu/gradposters2021_healthsciences/1006/thumbnail.jp

High On/Off Ratios in Bilayer Graphene Field Effect Transistors Realized by Surface Dopants

The unique property of bilayer graphene to show a band gap tunable by external electrical fields enables a variety of different device concepts with novel functionalities for electronic, optoelectronic and sensor applications. So far the operation of bilayer graphene based field effect transistors requires two individual gates to vary the channel's conductance and to create a band gap. In this paper we report on a method to increase the on/off ratio in single gated bilayer graphene field effect transistors by adsorbate doping. The adsorbate dopants on the upper side of the graphene establish a displacement field perpendicular to the graphene surface breaking the inversion symmetry of the two graphene layers. Low temperature measurements indicate, that the increased on/off ratio is caused by the opening of a mobility gap. Beside field effect transistors the presented approach can also be employed for other bilayer graphene based devices like photodetectors for THz to infrared radiation, chemical sensors and in more sophisticated structures such as antidot- or superlattices where an artificial potential landscape has to be created.Comment: 4 pages, 4 figure

Describing interruptions, multi-tasking and task-switching in the community pharmacy: A qualitative study in England

Background: There is growing evidence base around interruptions and distractions in the community pharmacy setting. There is also evidence to suggest these practices may be associated with dispensing errors. Up to date, qualitative research on this subject is limited. Objective: To explore interruptions and distractions in the community setting; utilising an ethnographic approach to be able to provide a detailed description of the circumstances surrounding such practices. Setting: Community pharmacies in England, July to October 2011. Method: An ethnographic approach was taken. Non participant, unstructured observations were utilised to make records of pharmacists’ every activities. Case studies were formed by combining field notes with detailed information on pharmacists and their respective pharmacy businesses. Content analysis was undertaken both manually and electronically, utilising NVivo 10. Results: Response rate was 12% (n=11). Over fifteen days, a total of 123 hours and 58 minutes of observations were recorded in 11 separate pharmacies of 11 individual pharmacists. The sample was evenly split by gender (female n=6; male n=5) and pharmacy ownership (independent n=5; multiple n=6). Employment statuses included employee pharmacists (n=6), owners (n=4) and a locum (n=1). Average period of registration as a pharmacist was 19 years (range 5-39 years). Average prescriptions busyness of pharmacies ranged from 2,600 – 24,000 items dispensed per month. Two key themes were: “Interruptions and task-switching” and “distractions and multi-tasking.” All observed pharmacists’ work was dominated by interruptions, task-switches, distractions and multi-tasking, often to manage a barrage of conflicting demands. These practices were observed to be part of a deep-rooted culture in the community setting. Directional work maps illustrated the extent and direction of task switching employed by pharmacists. Conclusions: In this study pharmacists’ working practices were permeated by interruptions and multi-tasking. These practices are inefficient and potentially reduce patient safety in terms of dispensing accuracy

Graphene field-effect-transistors with high on/off current ratio and large transport band gap at room temperature

Graphene is considered to be a promising candidate for future nano-electronics due to its exceptional electronic properties. Unfortunately, the graphene field-effect-transistors (FETs) cannot be turned off effectively due to the absence of a bandgap, leading to an on/off current ratio typically around 5 in top-gated graphene FETs. On the other hand, theoretical investigations and optical measurements suggest that a bandgap up to a few hundred meV can be created by the perpendicular E-field in bi-layer graphenes. Although previous carrier transport measurements in bi-layer graphene transistors did indicate a gate-induced insulating state at temperature below 1 Kelvin, the electrical (or transport) bandgap was estimated to be a few meV, and the room temperature on/off current ratio in bi-layer graphene FETs remains similar to those in single-layer graphene FETs. Here, for the first time, we report an on/off current ratio of around 100 and 2000 at room temperature and 20 K, respectively in our dual-gate bi-layer graphene FETs. We also measured an electrical bandgap of >130 and 80 meV at average electric displacements of 2.2 and 1.3 V/nm, respectively. This demonstration reveals the great potential of bi-layer graphene in applications such as digital electronics, pseudospintronics, terahertz technology, and infrared nanophotonics.Comment: 3 Figure