27 research outputs found
Narrowband searches for continuous and long-duration transient gravitational waves from known pulsars in the LIGO-Virgo third observing run
Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours–months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets
Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run
Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society
A narrative review of health research capacity strengthening in low and middle-income countries: lessons for conflict-affected areas
Abstract Conducting health research in conflict-affected areas and other complex environments is difficult, yet vital. However, the capacity to undertake such research is often limited and with little translation into practice, particularly in poorer countries. There is therefore a need to strengthen health research capacity in conflict-affected countries and regions. In this narrative review, we draw together evidence from low and middle-income countries to highlight challenges to research capacity strengthening in conflict, as well as examples of good practice. We find that authorship trends in health research indicate global imbalances in research capacity, with implications for the type and priorities of research produced, equity within epistemic communities and the development of sustainable research capacity in low and middle-income countries. Yet, there is little evidence on what constitutes effective health research capacity strengthening in conflict-affected areas. There is more evidence on health research capacity strengthening in general, from which several key enablers emerge: adequate and sustained financing; effective stewardship and equitable research partnerships; mentorship of researchers of all levels; and effective linkages of research to policy and practice. Strengthening health research capacity in conflict-affected areas needs to occur at multiple levels to ensure sustainability and equity. Capacity strengthening interventions need to take into consideration the dynamics of conflict, power dynamics within research collaborations, the potential impact of technology, and the wider political environment in which they take place
Storie di cura. Medicina narrativa e medicina delle evidenze: l'integrazioone possibile
Il notevole interesse suscitato nel corso degli ultimi anni dalla Medicina basata sulle narrazioni trova probabilmente una spiegazione nella crisi profonda di credibilità che attraversa la biomedicina nel momento in cui il dispiegamento di tutta la sua enorme capacità tecnologica evidenzia i limiti intrinseci ad un approccio che sembra smarrire i fondamenti stessi dell’incontro clinico e della relazione terapeutica. La rappresentazione narrativa della malattia consente di mettere a confronto la diversa interpretazione della realtà clinica propria del paziente e del professionista sanitario, rivelando il carattere simbolico anche di ogni presunto discorso scientifico rispetto alla concreta esperienza del corpo, della sofferenza, della malattia. Si apre così la possibilità di considerare la malattia come una “rete di prospettive”, consentendo un incontro ed un dialogo fecondi che trasformano le storie di malattia in storie di cura, ovvero percorsi dialogici di costruzione congiunta dell’assistenza sanitaria (care).
Il volume presenta e discute con esperti di livello nazionale e internazionale i risultati della prima ricerca italiana sulle storie di malattia - condotta dall'autore presso l’AUSL di Reggio Emilia - che ha cercato di integrare l’approccio della medicina narrativa con quello della medicina basata sulle evidenze (EBM