Gravitational Lensing at Millimeter Wavelengths

With today's millimeter and submillimeter instruments observers use gravitational lensing mostly as a tool to boost the sensitivity when observing distant objects. This is evident through the dominance of gravitationally lensed objects among those detected in CO rotational lines at z>1. It is also evident in the use of lensing magnification by galaxy clusters in order to reach faint submm/mm continuum sources. There are, however, a few cases where millimeter lines have been directly involved in understanding lensing configurations. Future mm/submm instruments, such as the ALMA interferometer, will have both the sensitivity and the angular resolution to allow detailed observations of gravitational lenses. The almost constant sensitivity to dust emission over the redshift range z=1-10 means that the likelihood for strong lensing of dust continuum sources is much higher than for optically selected sources. A large number of new strong lenses are therefore likely to be discovered with ALMA, allowing a direct assessment of cosmological parameters through lens statistics. Combined with an angular resolution <0.1", ALMA will also be efficient for probing the gravitational potential of galaxy clusters, where we will be able to study both the sources and the lenses themselves, free of obscuration and extinction corrections, derive rotation curves for the lenses, their orientation and, thus, greatly constrain lens models.Comment: 69 pages, Review on quasar lensing. Part of a LNP Topical Volume on "Dark matter and gravitational lensing", eds. F. Courbin, D. Minniti. To be published by Springer-Verlag 2002. Paper with full resolution figures can be found at ftp://oden.oso.chalmers.se/pub/tommy/mmviews.ps.g

How do you measure trust in social institutions and health professionals? A systematic review of the literature (2012–2021)

The importance of measuring trust in health systems has been accentuated due to its correlation with important health outcomes aimed at reducing COVID-19 transmission. A systematic review published almost a decade ago identified gaps in measures including the lack of focus on trust in systems, inconsistency regarding the dimensionality of trust and need for research to strengthen the validity of measures. Given developments in our understandings of trust since its publication, we sought to identify new scales developed, existing ones adapted in response to identified gaps, and agendas for future research. Using the PRISMA approach for systematic reviews, we conducted a search in four databases. A total of 26 articles were assessed. Twelve new scales were identified, while 14 were adapted for different settings and populations. Literature continues to focus on measuring trust in health professionals rather than systems. Various shortcomings were identified, including some articles not mentioning the dimensions included in the scale and suboptimal use of validity and reliability testing and/or reporting. Moreover, a variety of terms were used for dimensions. Future research is needed to address these gaps and consequently, to understand their correlation with health behaviors and outcomes more accurately

Examining nurse-led dysphagia screening tools in the general medical hospital population

Introduction: Dysphagia screening tools have been routinely used to assess for risk of aspiration in the stroke population. Despite a 30 to 40% prevalence rate of oropharyngeal dysphagia in older general medical populations, routine dysphagia screening is uncommon and the clinical utility of existing screening tools has received little attention. The primary study objective was to investigate the validity of using the Gugging Swallowing Screen (GuSS) to screen for dysphagia risk in acute inpatient population. Methods: The GuSS was administered by trained nursing staff to all eligible adults inpatients (18+ years) admitted to medical and surgical wards in a metropolitan hospital. Accuracy of the GuSS as a screening tool was compared to clinical swallowing examination outcomes conducted by a qualified speech pathologist, and the Royal Brisbane and Women’s Hospital Dysphagia Screening Tool (RBWH DST). Results: Seventy-seven patients (mean age = 71.2 ± 14.6 years) completed the study. Fifteen participants were diagnosed with dysphagia as compared with 28 and 33 who screened positive for dysphagia risk on the GuSS and RBWH DST respectively. Sensitivity and specificity of the GuSS was 73.3% and 72.6%, with positive predictive value (PPV) of 39.2% and negative predictive value (NPV) of 91.8% (AUC = 0.73). Sensitivity and specificity of the RBWH DST were 86.7% and 67.8% respectively, with PPV of 39.3% and NPV of 95.4% (AUC = 0.772). Discussion: Neither dysphagia screening tool was found to be a good indicator of dysphagia risk. Both nurse-led tools tended to over-identify dysphagia risk. Further work is required to determine the best screening tool for the older general inpatient population.Griffith Health, School of Applied PsychologyNo Full Tex