1,655 research outputs found
Stacking-induced fluorescence increase reveals allosteric interactions through DNA
From gene expression to nanotechnology, understanding and controlling DNA requires a detailed knowledge of its higher order structure and dynamics. Here we take advantage of the environment-sensitive photoisomerization of cyanine dyes to probe local and global changes in DNA structure. We report that a covalently attached Cy3 dye undergoes strong enhancement of fluorescence intensity and lifetime when stacked in a nick, gap or overhang region in duplex DNA. This is used to probe hybridization dynamics of a DNA hairpin down to the single-molecule level. We also show that varying the position of a single abasic site up to 20 base pairs away modulates the dye–DNA interaction, indicative of through-backbone allosteric interactions. The phenomenon of stacking-induced fluorescence increase (SIFI) should find widespread use in the study of the structure, dynamics and reactivity of nucleic acids
Cameos of compassion: exploring compassionate care using secondary analysis of digital patients’ stories.
Patient stories have been identified as a powerful tool to improve quality of care. Healthtalk.org is a digital resource (specific health-related website) presenting patients’ experiences of illness and healthcare through trigger films, videos and articles. Data have been generated from narrative interviews conducted by experienced researchers, based at the Health Experiences Research Group (HERG), University of Oxford. Our project explored the potential use of secondary analysis of digital sources as a methodological innovation to develop as a tool for teaching compassion to nursing students. For that, a purposive sample of transcripts from the HERG archive were selected for secondary analysis. Patients expressed both positive and negative experiences of care. Positive themes included: continuity of care and attentiveness to the fundamentals of care. Negative themes were related to poor quality of care; ignoring patient and family needs; and not being available for patients and family when needed. We concluded that secondary analysis of narrative interviews provides a powerful resource for identifying positive and negative patient experiences for learning and teaching. These can be designed into a digital toolkit and used as a learning and teaching resource to develop staff and students’ reflexivity in relation to the values and leadership behaviours associated with compassionate care and positive practice
Land-mobile satellite communication system
A satellite communications system includes an orbiting communications satellite for relaying communications to and from a plurality of ground stations, and a network management center for making connections via the satellite between the ground stations in response to connection requests received via the satellite from the ground stations, the network management center being configured to provide both open-end service and closed-end service. The network management center of one embodiment is configured to provides both types of service according to a predefined channel access protocol that enables the ground stations to request the type of service desired. The channel access protocol may be configured to adaptively allocate channels to open-end service and closed-end service according to changes in the traffic pattern and include a free-access tree algorithm that coordinates collision resolution among the ground stations
The second US Naval Observatory CCD Astrograph Catalog (UCAC2)
The second USNO CCD Astrograph Catalog, UCAC2 was released in July 2003.
Positions and proper motions for 48,330,571 sources (mostly stars) are
available on 3 CDs, supplemented with 2MASS photometry for 99.5% of the
sources. The catalog covers the sky area from -90 to +40 degrees declination,
going up to +52 in some areas; this completely supersedes the UCAC1 released in
2001. Current epoch positions are obtained from observations with the USNO
8-inch Twin Astrograph equipped with a 4k CCD camera. The precision of the
positions are 15 to 70 mas, depending on magnitude, with estimated systematic
errors of 10 mas or below. Proper motions are derived by utilizing over 140
ground-and space-based catalogs, including Hipparcos/Tycho, the AC2000.2, as
well as yet unpublished re-measures of the AGK2 plates and scans from the NPM
and SPM plates. Proper motion errors are about 1 to 3 mas/yr for stars to 12th
magnitude, and about 4 to 7 mas/yr for fainter stars to 16th magnitude. The
observational data, astrometric reductions, results, and important information
for the users of this catalog are presented.Comment: accepted by AJ, AAS LaTeX, 14 figures, 10 table
An exploration of the experiences and utility of functional electrical stimulation for foot drop in people with multiple sclerosis
Purpose: Functional electrical stimulation (FES) is effective in improving walking in people with multiple sclerosis (MS) with foot drop. There is limited research exploring people’s experiences of using this device. This study aims to explore the utility, efficacy, acceptability, and impact on daily life of the device in people with MS.
Methods: An interpretative phenomenological approach was employed. Ten participants who had used FES for 12 months were interviewed. Transcripts were analysed, and emergent themes identified.
Results: Nine participants continued to use the device. Three relevant super-ordinate themes were identified; impact of functional electrical stimulation, sticking with functional electrical stimulation, and autonomy and control. Participants reported challenges using the device; however, all reported positive physical and psychological benefits. Intrinsic and external influences such as; access to professional help, the influence of others, an individual’s ability to adapt, and experiences using the device, influenced their decisions to continue with the device. A thematic model of these factors was developed.
Conclusions: This study has contributed to our understanding of people with MS experiences of using the device and will help inform prescribing decisions and support the continued, appropriate use of FES over the longer term
Exploring Zeptosecond Quantum Equilibration Dynamics: From Deep-Inelastic to Fusion-Fission Outcomes in Ni+Ni Reactions
Energy dissipative processes play a key role in how quantum many-body systems
dynamically evolve towards equilibrium. In closed quantum systems, such
processes are attributed to the transfer of energy from collective motion to
single-particle degrees of freedom; however, the quantum many-body dynamics of
this evolutionary process are poorly understood. To explore energy dissipative
phenomena and equilibration dynamics in one such system, an experimental
investigation of deep-inelastic and fusion-fission outcomes in the
Ni+Ni reaction has been carried out. Experimental outcomes have
been compared to theoretical predictions using Time Dependent Hartree Fock and
Time Dependent Random Phase Approximation approaches, which respectively
incorporate one-body energy dissipation and fluctuations. Excellent
quantitative agreement has been found between experiment and calculations,
indicating that microscopic models incorporating one-body dissipation and
fluctuations provide a potential tool for exploring dissipation in low-energy
heavy ion collisions.Comment: 11 pages, 9 figures, 1 table, including Supplemental Material -
Version accepted for publication in Physical Review Letter
Emerging from the third space chrysalis: Experiences in a non-hierarchical, collaborative research community of practice
This article discusses the creation of a research-focused virtual community of practice (vCoP) for geographically-dispersed third space professionals, motivated by desires for enhanced professional collaboration, visibility and identity. The authors used collaborative autoethnography (CAE) to evaluate their personal reflections as vCoP participants. Data were gathered in two collaborative writing activities and analysed using thematic analysis (TA). The TA identified two connected themes, which capture the vCoP members’ aspirations to transcend their current roles and be research-active through connecting with like-minded professionals. Collaborative writing activities, including authoring this paper, cultivated elements of academic identity such as independence and purpose. A non-hierarchical and supportive vCoP environment allowed the members to work beyond time and institutional constraints to foster the evolution of the community and an emerging sense of professional identity beyond that typically associated with third space roles. The paper offers a model of collaboration that could help groups in similar situations
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