We use 47 gravitational wave sources from the Third LIGO–Virgo–Kamioka Gravitational Wave Detector Gravitational Wave Transient Catalog (GWTC–3) to estimate the Hubble parameter H(z), including its current value, the Hubble constant H 0. Each gravitational wave (GW) signal provides the luminosity distance to the source, and we estimate the corresponding redshift using two methods: the redshifted masses and a galaxy catalog. Using the binary black hole (BBH) redshifted masses, we simultaneously infer the source mass distribution and H(z). The source mass distribution displays a peak around 34 M ⊙, followed by a drop-off. Assuming this mass scale does not evolve with the redshift results in a H(z) measurement, yielding H 0 = 68 − 8 + 12 km s − 1 Mpc − 1 (68% credible interval) when combined with the H 0 measurement from GW170817 and its electromagnetic counterpart. This represents an improvement of 17% with respect to the H 0 estimate from GWTC–1. The second method associates each GW event with its probable host galaxy in the catalog GLADE+, statistically marginalizing over the redshifts of each event’s potential hosts. Assuming a fixed BBH population, we estimate a value of H 0 = 68 − 6 + 8 km s − 1 Mpc − 1 with the galaxy catalog method, an improvement of 42% with respect to our GWTC–1 result and 20% with respect to recent H 0 studies using GWTC–2 events. However, we show that this result is strongly impacted by assumptions about the BBH source mass distribution; the only event which is not strongly impacted by such assumptions (and is thus informative about H 0) is the well-localized event GW190814.

Quality of life among frail older people Background: Frailty has a great impact in the wellbeing of older people. Aim: To evaluate the quality of life of older people with and without frailty. Material and Methods: We assessed sociodemographic variables, health, integral geriatric assessment, quality of life using the WHOQoL-BREF questionnaire and the level of fragility using the Tilburg Frailty Indicator (TFI) in 538 participants. Results: Three hundred and five participants aged 73 ± 7 years (229 women) were classified as fragile and 233 aged 72 ± 6 years (125 women) as not having frailty. Compared with their non-fragile counterparts, frail participants had a lower number of years attending school (5.9 and 7.4 respectively), a lower Barther index (93.6 and 98.3 respectively), a lower mini mental score (21.9 and 22.8 respectively) and a higher Yessavage depression score (2.0 and 0.8 respectively). Also, frail participants had a significantly lower total quality of life score and significantly lower scores in the physical and psychological domains. No differences were observed for the social and environmental domains. Older frail participants used health services more frequently than their non-fragile counterparts. Conclusions: In this sample, frailty was associated with a lower quality of life and worse scores in several geriatric assessment tools.

Objective. The study sought to compare community-dwelling older people with respect to their level of physical activity and to the fear of falls between a group of sedentary elderly and a group of active elderly. Methods. Cross-sectional descriptive study carried out with 113 community-dwelling older people (45 sedentary and 48 active), users of an outpatient care center of the private health system with a geriatric program in Santiago, Chile. The study measured socio-demographic variables, state of health, comprehensive geriatric assessment, exercise, depression with the Yesavage scale, and fear of falling with the Short Falls Efficacy Scale - International (Short FES-I). Results. Sedentary older people have significantly higher scores in the Yesavage depression scale compared with active older people (4.2 versus 0.8). No statistically significant differences were found when comparing both groups of sedentary and active participants in terms of socio-demographic variables along with health, and functional and cognitive capacity. Regarding the fear of falling, the sedentary had a slightly higher score than the active (12 versus 11), although not significant. Conclusion. This study showed that fear of falling was equal in sedentary and active older people who live in the community, although it was found that sedentary individuals had a higher risk of having a positive screening for geriatric depression in those participants who do not perform physical activity.

<strong>Introducción</strong><span>: La inserción de estudiantes de pregrado en actividades de investigación es relevante para fomentar la crítica y aplicación de resultados de investigación. La formación de ayudantes de investigación se plantea como una alternativa válida para que los alumnos se expongan, experimenten y participen activamente en el proceso de investigación.</span><br /><strong>Objetivo</strong><span>: Identificar el nivel de conocimiento y grado de satisfacción de los estudiantes después de  participar en un programa de formación de ayudantes de investigación. </span><em>Método</em><span>: Estudio de pre y post test en 20 estudiantes de pregrado de Enfermería. Se evaluó el conocimiento alcanzado y la satisfacción de los estudiantes con el  programa de formación, el cual considera  tres módulos de aprendizaje distribuidos en 180 horas cronológicas.</span><br /><strong>Resultados</strong><span>: El conocimiento de los estudiantes incrementó significativamente con el programa, no se relacionó con el conocimiento que el alumno trae al inicio del mismo, así como tampoco con el semestre que cursa. El grado de satisfacción fue en el 100% de los alumnos muy satisfecho.</span><br /><strong>Discusión</strong><em>:</em><span> Este artículo reporta un programa de formación de ayudantes de investigación que es posible ser replicado en otras realidades, que incrementa el conocimiento, con un alto grado de satisfacción en los estudiantes. La duración del programa podría considerarse una debilidad.</span><br /><strong>Conclusión</strong><em>:</em><span> La participación de estudiantes de pregrado en un programa de formación de ayudantes de investigación, puede considerarse una estrategia para involucrar a alumnos en investigación, y que valoren su aporte en la disciplina de enfermería.</span>

seguramente con mayor destreza, pero no con más amor que yo, su verdor y lozanía, para que sucesivas generaciones de jóvenes sigan recibiendo la influencia de su delicada frescura y la honda sugestión de su serena belleza".