1,072 research outputs found
What is the initiation step of the Grubbs-Hoveyda olefin metathesis catalyst?
Density function theory calculations reveal that the Grubbs-Hoveyda olefin metathesis pre-catalyst is activated by the formation of a complex in which the incoming alkene substrate and outgoing alkoxy ligand are both clearly associated with the ruthenium centre. The computed energies for reaction are in good agreement with the experimental values, reported here
Digital Peer-Supported Self-Management Intervention Codesigned by People With Long COVID: Mixed Methods Proof-of-Concept Study.
BACKGROUND: There are around 1.3 million people in the United Kingdom with the devastating psychological, physical, and cognitive consequences of long COVID (LC). UK guidelines recommend that LC symptoms be managed pragmatically with holistic support for patients' biopsychosocial needs, including psychological, emotional, and physical health. Self-management strategies, such as pacing, prioritization, and goal setting, are vital for the self-management of many LC symptoms. OBJECTIVE: This paper describes the codevelopment and initial testing of a digital intervention combining peer support with positive psychology approaches for self-managing the physical, emotional, psychological, and cognitive challenges associated with LC. The objectives of this study were to (1) codesign an intervention with and for people with LC; (2) test the intervention and study methods; (3) measure changes in participant well-being, self-efficacy, fatigue, and loneliness; and (4) understand the types of self-management goals and strategies used by people with LC. METHODS: The study used a pre-post, mixed methods, pragmatic, uncontrolled design. Digital intervention content was codeveloped with a lived-experience group to meet the needs uncovered during the intervention development and logic mapping phase. The resulting 8-week digital intervention, Hope Programme for Long COVID, was attended by 47 participants, who completed pre- and postprogram measures of well-being, self-efficacy, fatigue, and loneliness. Goal-setting data were extracted from the digital platform at the end of the intervention. RESULTS: The recruitment rate (n=47, 83.9%) and follow-up rate (n=28, 59.6%) were encouraging. Positive mental well-being (mean difference 6.5, P<.001) and self-efficacy (mean difference 1.1, P=.009) improved from baseline to postcourse. All goals set by participants mapped onto the 5 goal-oriented domains in the taxonomy of everyday self-management strategies (TEDSS). The most frequent type of goals was related to activity strategies, followed by health behavior and internal strategies. CONCLUSIONS: The bespoke self-management intervention, Hope Programme for Long COVID, was well attended, and follow-up was encouraging. The sample characteristics largely mirrored those of the wider UK population with LC. Although not powered to detect statistically significant changes, the preliminary data show improvements in self-efficacy and positive mental well-being. Our next trial (ISRCTN: 11868601) will use a nonrandomized waitlist control design to further examine intervention efficacy
âItâs like equality now; itâs not as if itâs the old daysâ: an investigation into gender identity development and football participation of adolescent girls
This article explores the influence participating in football has on the development of adolescent girlsâ gender identity, an area which currently lacks academic attention. Data were taken from an ethnographic study with a group of adolescent girls and boys and compared to Jeanesâ research. A social constructionist framework was deployed with links to both critical theory and feminist literature. Qualitative and participatory methods were used to fully engage with the complex issue of gender identity. The girls within this study were aware of the normative gender expectations linked to âbeing a femaleâ but did not find this restrictive. The girls moved between many changing identities and organised their âweb of selvesâ accordingly. The apparent need to measure success by the parameters of male standards created a barrier to girlsâ identity development
Toward a simulation approach for alkene ring-closing metathesis : scope and limitations of a model for RCM
A published model for revealing solvent effects on the ring-closing metathesis (RCM) reaction of di-Et diallylmalonate 7 has been evaluated over a wider range of conditions, to assess its suitability for new applications. Unfortunately, the model is too flexible and the published rate consts. do not agree with exptl. studies in the literature. However, by fixing the values of important rate consts. and restricting the concn. ranges studied, useful conclusions can be drawn about the relative rates of RCM of different substrates, precatalyst concn. can be simulated accurately and the effect of precatalyst loading can be anticipated. Progress has also been made toward applying the model to precatalyst evaluation, but further modifications to the model are necessary to achieve much broader aims
Bostonia: The Boston University Alumni Magazine. Volume 9
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
Photometric variability of the T Tauri star TW Hya on time scales of hours to years
MOST (Microvariability & Oscillations of STars) and ASAS (All Sky Automated
Survey) observations have been used to characterize photometric variability of
TW Hya on time scales from a fraction of a day to 7.5 weeks and from a few days
to 8 years, respectively. The two data sets have very different uncertainties
and temporal coverage properties and cannot be directly combined, nevertheless,
they suggests a global variability spectrum with "flicker noise" properties,
i.e. with amplitudes a ~ 1/sqrt(f), over >4 decades in frequency, in the range
f = 0.0003 to 10 cycles per day (c/d). A 3.7 d period is clearly present in the
continuous 11 day, 0.07 d time resolution, observations by MOST in 2007.
Brightness extrema coincide with zero-velocity crossings in periodic (3.56 d)
radial velocity variability detected in contemporaneous spectroscopic
observations of Setiawan et al. (2008) and interpreted as caused by a planet.
The 3.56/3.7 d periodicity was entirely absent in the second, four times longer
MOST run in 2008, casting doubt on the planetary explanation. Instead, a
spectrum of unstable single periods within the range of 2 - 9 days was
observed; the tendency of the periods to progressively shorten was well traced
using the wavelet analysis. The evolving periodicities and the overall
flicker-noise characteristics of the TW Hya variability suggest a combination
of several mechanisms, with the dominant ones probably related to the accretion
processes from the disk around the star.Comment: MNRAS submitte
Local semicircle law at the spectral edge for Gaussian -ensembles
We study the local semicircle law for Gaussian -ensembles at the edge
of the spectrum. We prove that at the almost optimal level of
, the local semicircle law holds for all at
the edge. The proof of the main theorem relies on the calculation of the
moments of the tridiagonal model of Gaussian -ensembles up to the
-moment where . The result is the analogous to
the result of Sinai and Soshnikov for Wigner matrices, but the combinatorics
involved in the calculations are different.Comment: 16 pages, 2 figure
Catalog of Galactic Beta Cephei Stars
We present an extensive and up-to-date catalog of Galactic Beta Cephei stars.
This catalog is intended to give a comprehensive overview of observational
characteristics of all known Beta Cephei stars. 93 stars could be confirmed to
be Beta Cephei stars. For some stars we re-analyzed published data or conducted
our own analyses. 61 stars were rejected from the final Beta Cephei list, and
77 stars are suspected to be Beta Cephei stars. A list of critically selected
pulsation frequencies for confirmed Beta Cephei stars is also presented. We
analyze the Beta Cephei stars as a group, such as the distributions of their
spectral types, projected rotational velocities, radial velocities, pulsation
periods, and Galactic coordinates. We confirm that the majority of these stars
are multiperiodic pulsators. We show that, besides two exceptions, the Beta
Cephei stars with high pulsation amplitudes are slow rotators. We construct a
theoretical HR diagram that suggests that almost all 93 Beta Cephei stars are
MS objects. We discuss the observational boundaries of Beta Cephei pulsation
and their physical parameters. We corroborate that the excited pulsation modes
are near to the radial fundamental mode in frequency and we show that the mass
distribution of the stars peaks at 12 solar masses. We point out that the
theoretical instability strip of the Beta Cephei stars is filled neither at the
cool nor at the hot end and attempt to explain this observation
IdentificaciĂłn del Ăndice de vulnerabilidad territorial a partir de modelos jerĂĄrquicos y heurĂsticos aplicando SOA
Auxiliar de InvestigaciĂłnEn el proyecto se realiza el diseño y desarrollo de 4 servicios web implementando los modelos de toma de decisiĂłn (AHP, AHP FUZZY, ELECTRE y PROMETHEE), encargados de procesar datos obtenidos en campo en la primera fase del proyecto que se realizĂł a travĂ©s de encuestas, formatos de entrevistas, talleres y metodologĂas de anĂĄlisis. Los datos se procesaran de acuerdo al modelo de toma de decisiĂłn seleccionado, generando como resultado final un indicador de vulnerabilidad territorial.PregradoIngeniero de Sistema
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