Social network assessment in community-dwelling older persons: results from a study of three European populations

Background and aims: In clinical practice, the status of living alone is often used as the only measure describing an older person's social network. We evaluated whether additional use of a brief social network measure provides relevant additional information in relation to social support and engagement. Methods: Cross-sectional survey of 6982 community-dwelling adults 65 years or older living in London, UK; Hamburg, Germany; and Solothurn, Switzerland. Data were collected using the self-administered multidimensional Health Risk Appraisal Questionnaire. Multivariate models were used to analyse adjusted correlations between the two measures of social network (living alone status, risk for social isolation with marginal family and friend network subscales) and potential consequences of inadequate social network (marginal emotional or instrumental support, lack of social engagement). Results: Living alone status was more strongly associated with marginal instrumental support [OR=7.6 (95% CI 6.3, 9.1)] than with marginal emotional support [OR=4.2 (95% CI 3.4, 5.1)], and showed no statistically significant association with lack of social engagement [OR=0.9 (95% CI 0.8, 1.0)]. Risk of social isolation was more strongly related to marginal emotional support [OR=6.6 (95% CI 5.4, 8.0)] than to marginal instrumental support [OR=3.3 (95% CI 2.8, 4.0)], and was moderately related to lack of social engagement [OR=2.9 (95% CI 2.5, 3.4]. Marginal family and friend network subscales showed consistent and unique associations with social support and social engagement. Conclusion: Findings suggest that living alone status and a brief measure of social network identifies distinctive at-risk groups and potential pathways for intervention. Geriatric assessment programs including both social network measures may provide useful information about potentially modifiable social network risks in older person

Venus Evolution Through Time: Key Science Questions, Selected Mission Concepts and Future Investigations

In this work we discuss various selected mission concepts addressing Venus evolution through time. More specifically, we address investigations and payload instrument concepts supporting scientific goals and open questions presented in the companion articles of this volume. Also included are their related investigations (observations & modeling) and discussion of which measurements and future data products are needed to better constrain Venus’ atmosphere, climate, surface, interior and habitability evolution through time. A new fleet of Venus missions has been selected, and new mission concepts will continue to be considered for future selections. Missions under development include radar-equipped ESA-led EnVision M5 orbiter mission (European Space Agency 2021), NASA-JPL’s VERITAS orbiter mission (Smrekar et al. 2022a), NASA-GSFC’s DAVINCI entry probe/flyby mission (Garvin et al. 2022a). The data acquired with the VERITAS, DAVINCI, and EnVision from the end of this decade will fundamentally improve our understanding of the planet’s long term history, current activity and evolutionary path. We further describe future mission concepts and measurements beyond the current framework of selected missions, as well as the synergies between these mission concepts, ground-based and space-based observatories and facilities, laboratory measurements, and future algorithmic or modeling activities that pave the way for the development of a Venus program that extends into the 2040s (Wilson et al. 2022)

The environmental effects of very large bolide impacts on early Mars explored with a hierarchy of numerical models

International audienceThe origin of the presence of geological and mineralogical evidence that liquid water flowed on the surface of early Mars is now a 50-year-old mystery. It has been proposed (Segura et al., 2002, 2008, 2012) that bolide impacts could have triggered a long-term climate change, producing precipitation and runoff that may have altered the surface of Mars in a way that could explain (at least part of) this evidence. Here we use a hierarchy of numerical models (a 3-D Global Climate Model, a 1-D radiative-convective model and a 2-D Mantle Dynamics model) to test that hypothesis and more generally explore the environmental effects of very large bolide impacts (Dimpactor > 100 km, or Dcrater > 600 km) on the atmosphere, surface and interior of early Mars.Using a combination of 1-D and 3-D climate simulations, we show that the environmental effects of the largest impact events recorded on Mars are characterized by: (i) a short impact-induced warm period (several tens of Earth years for the surface and atmosphere to be back to ambient conditions after very large impact events); (ii) a low amount of hydrological cycling of water (because the evaporation of precipitation that reached the ground is extremely limited). The total cumulative amount of precipitation (rainfall) can be reasonably well approximated by the initial post-impact atmospheric reservoir of water vapour (coming from the impactor, the impacted terrain and from the sublimation of permanent ice reservoirs heated by the hot ejecta layer); (iii) deluge-style precipitation (∼2.6 m Global Equivalent Layer of surface precipitation per Earth year for our reference simulation, quantitatively in agreement with previous 1-D cloud free climate calculations of Segura et al., 2002), and (iv) precipitation patterns that are uncorrelated with the observed regions of valley networks.However, we show that the impact-induced stable runaway greenhouse state predicted by Segura et al. (2012) should not be achievable if convection and water vapour condensation processes are considered. We nevertheless confirm the results of Segura et al. (2008) and Urata and Toon (2013) that water ice clouds could in theory significantly extend the duration of the post-impact warm period, and even for cloud coverage significantly lower than predicted in Ramirez and Kasting (2017). However, the range of cloud microphysical properties for which this scenario works is very narrow.Using 2-D Mantle Dynamics simulations we find that large bolide impacts can produce a strong thermal anomaly in the mantle of Mars that can survive and propagate for tens of millions of years. This thermal anomaly could raise the near-surface internal heat flux up to several hundreds of mW/m2 (i.e. up to ∼10 times the ambient flux) for several millions years at the edges of the impact crater. However, such internal heat flux is largely insufficient to keep the martian surface above the melting point of water.In addition to the poor temporal correlation between the formation of the largest basins and valley networks (Fassett and Head, 2011), these arguments indicate that the largest impact events are unlikely to be the direct cause of formation of the Noachian valley networks. Our numerical results support instead the prediction of Palumbo and Head (2018) that very large impact-induced rainfall could have caused degradation of large craters, erased small craters, and formed smooth plains, potentially erasing much of the previously visible morphological surface history. Such hot rainfalls may have also led to the formation of aqueous alteration products on Noachian-aged terrains, which is consistent with the timing of formation of clays

Performance of an abbreviated version of the Lubben Social Network Scale among three European community-dwelling older adult populations

PURPOSE: There is a need for valid and reliable short scales that can be used to assess social networks and social supports and to screen for social isolation in older persons. DESIGN AND METHODS: The present study is a cross-national and cross-cultural evaluation of the performance of an abbreviated version of the Lubben Social Network Scale (LSNS-6), which was used to screen for social isolation among community-dwelling older adult populations in three European countries. Based on the concept of lack of redundancy of social ties we defined clinical cut-points of the LSNS-6 for identifying persons deemed at risk for social isolation. RESULTS: Among all three samples, the LSNS-6 and two subscales (Family and Friends) demonstrated high levels of internal consistency, stable factor structures, and high correlations with criterion variables. The proposed clinical cut-points showed good convergent validity, and classified 20% of the respondents in Hamburg, 11% of those in Solothurn (Switzerland), and 15% of those in London as at risk for social isolation. IMPLICATIONS: We conclude that abbreviated scales such as the LSNS-6 should be considered for inclusion in practice protocols of gerontological practitioners. Screening older persons based on the LSNS-6 provides quantitative information on their family and friendship ties, and identifies persons at increased risk for social isolation who might benefit from in-depth assessment and targeted interventions