651 research outputs found
A probabilistic approach to some results by Nieto and Truax
In this paper, we reconsider some results by Nieto and Truax about generating
functions for arbitrary order coherent and squeezed states. These results were
obtained using the exponential of the Laplacian operator; more elaborated
operational identities were used by Dattoli et al. \cite{Dattoli} to extend
these results. In this note, we show that the operational approach can be
replaced by a purely probabilistic approach, in the sense that the exponential
of derivatives operators can be identified with equivalent expectation
operators. This approach brings new insight about the kinks between operational
and probabilistic calculus.Comment: 2nd versio
On the creation of near-surface nitrogen-vacancy centre ensembles by implantation of type Ib diamond
Dense, near-surface (within 10 nm) ensembles of nitrogen-vacancy (NV) centres
in diamond are rapidly moving into prominence as the workhorse of a variety of
envisaged applications, ranging from the imaging of fast-fluctuating magnetic
signals to the facilitation of nuclear hyperpolarisation. Unlike their bulk
counterparts, near-surface ensembles suffer from charge stability issues and
reduced NV formation efficiency due to the diamond surface's role as a vacancy
sink during annealing and an electron sink afterwards. To this end, work is
ongoing to determine the best methods for producing high-quality ensembles in
this regime. Here we examine the prospects for creating such ensembles
cost-effectively by implanting nitrogen-rich type Ib diamond with electron
donors, aiming to exploit the high bulk nitrogen density to combat
surface-induced band bending in the process. This approach has previously been
successful at creating deeper ensembles, however we find that in the
near-surface regime there are fewer benefits over nitrogen implantation into
pure diamond substrates. Our results suggest that control over diamond surface
termination during annealing is key to successfully creating high-yield
near-surface NV ensembles generally, and implantation into type Ib diamond may
be worth revisiting once that has been accomplished.Comment: 7 pages, 3 figure
Critical reflexivity and decolonial methodology in islandstudies: interrogating the scholar within
Although the field of island studies has from the start regarded itself as a defender of islands and islander interests, it is entangled in coloniality. This editorial focuses on issues of power, knowledge, and position. Who wields power in island studies? Who knows about islands? Where is island studies located, and how does it position itself? The paper discusses problems such as tokenism and forced inclusions, denial and circumscription of expertise, and onto-epistemological discrimination and hegemony within island studies. Ultimately, the paper advances the need for critical reflexivity and decolonial methodology within island studies, for pluralistic approaches to inclusivity and recognition of epistemic differences.Asian Studie
An Adjoint-based Derivative Evaluation Method for Time-dependent Aeroelastic Optimization of Flexible Aircraft
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106483/1/AIAA2013-1530.pd
Capturing the wisdom of the crowd: health professions’ educators meet at a virtual world café
Background: Conversations about educational challenges and potential solutions among a globally and culturally diverse group of health professions’ educators can facilitate identity formation, mentoring relationships and professional network building. The COVID-19 pandemic has made it even more important to co-create and disseminate knowledge, specifically regarding online and flexible learning formats. Approach: Based on the principles of social learning, we combined speed mentoring and world café formats to offer a virtual Zoom™ workshop, with large and small group discussions, to reach health professions’ educators across the globe. The goal was to establish a psychologically safe space for dialogue regarding adaptation to online teaching-learning formats. Evaluation: We aimed to establish psychological safety to stimulate thought-provoking discussions within the various small groups and obtain valuable contributions from participants. From these conversations, we were able to formulate ‘hot tips’ on how to adapt to (sometimes new) online teaching-learning formats while nurturing teacher and student wellbeing. Reflection: Through this virtual workshop we realized that despite contextual differences, many challenges are common worldwide. We experienced technological difficulties during the session, which needed rapid adaptation by the organising team. We encouraged, but did not pressure, participants to use video and audio during breakout discussions as we wanted them to feel safe and comfortable. The large audience size and different time zones were challenging; therefore, leadership had to be resilient and focussed. Although this virtual format was triggered by the pandemic, the format can be continued in the future to discuss other relevant global education topics
Clinical and budget impacts of changes in oral anticoagulation prescribing for atrial fibrillation
OBJECTIVE: To assess temporal clinical and budget impacts of changes in atrial fibrillation (AF)-related prescribing in England. METHODS: Data on AF prevalence, AF-related stroke incidence and prescribing for all National Health Service general practices, hospitals and registered patients with hospitalised AF-related stroke in England were obtained from national databases. Stroke care costs were based on published data. We compared changes in oral anticoagulation prescribing (warfarin or direct oral anticoagulants (DOACs)), incidence of hospitalised AF-related stroke, and associated overall and per-patient costs in the periods January 2011-June 2014 and July 2014-December 2017. RESULTS: Between 2011-2014 and 2014-2017, recipients of oral anticoagulation for AF increased by 86.5% from 1 381 170 to 2 575 669. The number of patients prescribed warfarin grew by 16.1% from 1 313 544 to 1 525 674 and those taking DOACs by 1452.7% from 67 626 to 1 049 995. Prescribed items increased by 5.9% for warfarin (95% CI 2.9% to 8.9%) but by 2004.8% for DOACs (95% CI 1848.8% to 2160.7%). Oral anticoagulation prescription cost rose overall by 781.2%, from £87 313 310 to £769 444 028, (£733,466,204 with warfarin monitoring) and per patient by 50.7%, from £293 to £442, giving an incremental cost of £149. Nevertheless, as AF-related stroke incidence fell by 11.3% (95% CI -11.5% to -11.1%) from 86 467 in 2011-2014 to 76 730 in 2014-2017 with adjustment for AF prevalence, the overall per-patient cost reduced from £1129 to £840, giving an incremental per-patient saving of £289. CONCLUSIONS: Despite nearly one million additional DOAC prescriptions and substantial associated spending in the latter part of this study, the decline in AF-related stroke led to incremental savings at the national level
A Novel Splice-Site Mutation in VEGFC Is Associated with Congenital Primary Lymphoedema of Gordon.
Lymphedema is characterized by chronic swelling of any body part caused by malfunctioning or obstruction in the lymphatic system. Primary lymphedema is often considered genetic in origin. VEGFC, which is a gene encoding the ligand for the vascular endothelial growth factor receptor 3 (VEGFR3/FLT4) and important for lymph vessel development during lymphangiogenesis, has been associated with a specific subtype of primary lymphedema. Through Sanger sequencing of a proband with bilateral congenital pedal edema resembling Milroy disease, we identified a novel mutation (NM_005429.2; c.361+5G>A) in VEGFC. The mutation induced skipping of exon 2 of VEGFC resulting in a frameshift and the introduction of a premature stop codon (p.Ala50ValfsTer18). The mutation leads to a loss of the entire VEGF-homology domain and the C-terminus. Expression of this Vegfc variant in the zebrafish floorplate showed that the splice-site variant significantly reduces the biological activity of the protein. Our findings confirm that the splice-site variant, c.361+5G>A, causes the primary lymphedema phenotype in the proband. We examine the mutations and clinical phenotypes of the previously reported cases to review the current knowledge in this area
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