Seeing Double at Neptune's South Pole

Keck near-infrared images of Neptune from UT 26 July 2007 show that the cloud feature typically observed within a few degrees of Neptune's south pole had split into a pair of bright spots. A careful determination of disk center places the cloud centers at -89.07 +/- 0 .06 and -87.84 +/- 0.06 degrees planetocentric latitude. If modeled as optically thick, perfectly reflecting layers, we find the pair of features to be constrained to the troposphere, at pressures greater than 0.4 bar. By UT 28 July 2007, images with comparable resolution reveal only a single feature near the south pole. The changing morphology of these circumpolar clouds suggests they may form in a region of strong convection surrounding a Neptunian south polar vortex.Comment: 10 pages, 7 figures; accepted to Icaru

Retrieving Neptune's aerosol properties from Keck OSIRIS observations. I. Dark regions

We present and analyze three-dimensional data cubes of Neptune from the OSIRIS integral-field spectrograph on the 10-m Keck telescope, from July 2009. These data have a spatial resolution of 0.035"/pixel and spectral resolution of R~3800 in the H and K broad bands. We focus our analysis on regions of Neptune's atmosphere that are near-infrared dark- that is, free of discrete bright cloud features. We use a forward model coupled to a Markov chain Monte Carlo algorithm to retrieve properties of Neptune's aerosol structure and methane profile above ~4 bar in these near-infrared dark regions. Using a set of high signal-to-noise spectra in a cloud-free band from 2-12N, we find that Neptune's cloud opacity is dominated by a compact, optically thick cloud layer with a base near 3 bar and composed of low albedo, forward scattering particles, with an assumed characteristic size of ~1$\mu$m. Above this cloud, we require a vertically extended haze of smaller (~0.1 $\mu$m) particles, which reaches from the upper troposphere (~0.6 bar) into the stratosphere. The particles in this haze are brighter and more isotropically scattering than those in the deep cloud. When we extend our analysis to 18 cloud-free locations from 20N to 87S, we observe that the optical depth in aerosols above 0.5 bar decreases by a factor of 2-3 or more at mid- and high-southern latitudes relative to low latitudes. We also consider Neptune's methane (CH$_4$) profile, and find that our retrievals indicate a strong preference for a low methane relative humidity at pressures where methane is expected to condense. Our preferred solution at most locations is for a methane relative humidity below 10% near the tropopause in addition to methane depletion down to 2.0-2.5 bar. We tentatively identify a trend of lower CH$_4$ columns above 2.5 bar at mid- and high-southern latitudes over low latitudes.Comment: Published in Icarus: 15 September 201

Longitudinal associations between activity and cognition vary by age, activity type, and cognitive domain

The demonstration of correlated change is critical to understanding the relationship between activity engagement and cognitive functioning in older adulthood. Changes in activity have been shown to be related to changes in cognition, but little attention has been devoted to how this relationship may vary between specific activity types, cognitive domains, and age groups. Participants initially aged 65−98 years (M = 77.46 years) from the Australian Longitudinal Study of Ageing (n = 1,321) completed measurements of activity (i.e., cognitive, group social, one-on-one social, and physical) and cognition (i.e., perceptual speed, and immediate and delayed episodic memory) at baseline, 2, 8, 11, and 15 years later. Bivariate latent growth curve models covarying for education, sex, and baseline age and medical conditions revealed multiple positive-level relations between activity and cognitive performance, but activity level was not related to later cognitive change. Change in perceptual speed over 15 years was positively associated with change in cognitive activity, and change in immediate episodic memory was positively associated with change in one-on-one social activity. Old-old adults showed a stronger change−change covariance for mentally stimulating activity in relation to perceptual speed than did young-old adults. The differentiation by activity type, cognitive domain, and age contributes to the growing evidence that there is variation in the way cognitive ability at different ages is related to activity.NHMRC Fellowship No. 1002560 and the ARC Centre of Excellence in Population Ageing Research (project # CE110001029)

The influence of smoking, sedentary lifestyle and obesity on cognitive impairment-free life expectancy

BACKGROUND Smoking, sedentary lifestyle and obesity are risk factors for mortality and dementia. However, their impact on cognitive impairment-free life expectancy (CIFLE)has not previously been estimated. METHODS Data were drawn from the DYNOPTA dataset which was derived by harmonizing and pooling common measures from five longitudinal ageing studies. Participants for whom the Mini-Mental State Examination was available were included (N¼8111,48.6% men). Data on education, sex, body mass index, smoking and sedentary lifestyle were collected and mortality data were obtained from Government Records via data linkage.Total life expectancy (LE), CIFLE and years spent with cognitive impairment (CILE)were estimated for each risk factor and total burden of risk factors. RESULTS CILE was approximately 2 years for men and 3 years for women, regardless of age. For men and women respectively, reduced LE associated with smoking was 3.82and 5.88 years, associated with obesity was 0.62 and 1.72 years and associated with being sedentary was 2.50 and 2.89 years. Absence of each risk factor was associated with longer LE and CIFLE, but also longer CILE for smoking in women and being sedentary in both sexes. Compared with participants with no risk factors, those with 2þ had shorter CIFLE of up to 3.5 years depending on gender and education level. CONCLUSIONS Population level reductions in smoking, sedentary lifestyle and obesity increase longevity and number of years lived without cognitive impairment. Years lived with cognitive impairment may also increase.This work was supported by a National Health and Medical Research Council grant # 410215 and by the Australian Research Council Centre of Excellence in Population Ageing Research (CE110001029). K.J.A is funded by NHMRC Fellowship #1002560. C.J. is funded by the AXA Research Fund

Influence of health locus of control on recovery of function in recently hospitalized frail older adults

"This is the peer reviewed version of the following article: [Milte, C. M., Luszcz, M. A., Ratcliffe, J., Masters, S. and Crotty, M. (2015), Influence of health locus of control on recovery of function in recently hospitalized frail older adults. Geriatrics & Gerontology International, 15: 341–349.], which has been published in final form at [http://dx.doi.org/10.1111/ggi.12281]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. http://olabout.wiley.com/WileyCDA/Section/id-820227.html#terms"AIM: To investigate the influence of health locus of control on physical function, quality of life, depression and satisfaction with care transition in a sample of older adults after a hospital admission. METHODS: A total of 230 older adults referred for transition care after a hospital admission (mean length of stay 25.7 days, SD 17.2) were recruited into a randomized controlled intervention trial investigating the effect of specialized coaching compared with usual care. Older adults completed the multidimensional health locus of control (MHLC) survey at baseline. Self-rated quality of life, depression and physical function were assessed at baseline and 12 months using the EuroQol five-dimension, Geriatric Depression Scale (GDS) and Modified Barthel Index (MBI), respectively. RESULTS: Results from hierarchical multiple regression analysis in 136 participants (70 usual care and 66 specialized care) with complete data showed that higher scores on the MHLC internal subscale were related to better quality of life, and better physical function in the usual care group at 12 months, but not depression or transition process satisfaction at 3 months. No relationships between MHLC subscales and outcome measures were observed in the specialized care group, where the coaching intervention might have precluded any relationship observed. CONCLUSIONS: A stronger sense of personal control over health was associated with better maintenance of quality of life and physical function at 12 months in older adults undergoing usual care transition after acute hospitalization. Modification of control beliefs has the potential to promote resilience and impact on health outcomes in older adults during care transitions

Breathlessness and sexual activity in older adults: The Australian Longitudinal Study of Ageing

© 2018 The Author(s). Sexual activity is important to older adults (65 +). Breathlessness affects about 25% of older adults but impact on sexual activity is unknown. We evaluated the relationships between breathlessness and sexual inactivity and self-reported health among older community-dwelling adults in the Australian Longitudinal Study of Ageing. Associations between self-reported breathlessness (hurrying on level ground or walking up a slight hill) at baseline, self-reported sexual activity, overall health and health compared to people of the same age were explored using logistic regression at baseline and 2 years, adjusted for potential confounders (age, sex, marital status, smoking status and co-morbidities). Of 798 participants (mean age 76.4 years [SD, 5.8] 65 to 103; 53% men, 73% married), 688 (86.2%) had 2-year follow-up data. People with breathlessness had higher prevalence and duration of sexual inactivity (77.7% vs. 65.6%; p < 0.001; 12 [IQR, 5-17] vs. 9.5 [IQR, 5-16] years; p = 0.043). Breathlessness was associated with more sexual inactivity, (adjusted OR 1.75; [95% CI] 1.24-2.45), worse health (adjusted OR 2.02; 1.53-2.67) and worse health compared to peers (adjusted OR 1.72; 1.25-2.38). Baseline breathlessness did not predict more sexual inactivity at 2 years. In conclusion, breathlessness contributes to sexual inactivity and worse perceived health in older adults, which calls for improved assessment and management

Cumulative Load of Depressive Symptoms Is Associated With Cortisol Awakening Response in Very Old Age.

This study examined links of cumulative and present depressive symptoms with present cortisol diurnal profiles in oldest-old adults. Five waves of data from 50 older adults (M age = 89.05 years; 64% women) who participated in the Australian Longitudinal Study of Ageing were used to combine 15 years of longitudinal data with seven cortisol samples per day over a one-week period. Findings revealed that individuals with more past depressive symptoms showed a lower cortisol awakening response (CAR). Interestingly, present depressive symptoms were not associated with the CAR. These findings inform our understanding of distal health factors in very old age

Gender differences in the trajectories of late-life depressive symptomology and probable depression in the years prior to death

BACKGROUND: Gender differences in depression are well established. Whether these differences persist into late life and in the years preceding death is less clear. There is a suggestion that there is no increased likelihood of depression in late life, but that there is an increase in depressive symptomology, particularly with proximity to death. We compared trajectories of probable depression and depressive symptomology between men and women over age and distance-to-death metrics to determine whether reports of depressive symptoms are more strongly related to age or mortality. METHODS: Participants (N = 2,852) from the Dynamic Analyses to Optimise Ageing (DYNOPTA) project had a mean age of 75 years (SD = 5.68 years) at baseline and were observed for up to 16 years prior to death. Multi-level regression models estimated change in depressive symptomology and probable depression over two time metrics, increasing age, and distance-to-death. RESULTS: Increases in depressive symptomology were reported over increasing age and in the years approaching death. Only male participants reported increased probable depression in the years preceding death. Models that utilized distance-to-death metrics better represented changes in late-life depression, although any changes in depression appear to be accounted for by co-varying physical health status. CONCLUSIONS: As death approaches, there are increases in the levels of depressive symptomology even after controlling for socio-demographic and health covariates. In line with increases in suicide rates in late life, male participants were at greater risk of reporting increases in depressive symptomology.NHMRC (National Health and Medical Research Council of Australia

Social networks and memory over 15 years of followup in a cohort of older Australians: Results from the Australian Longitudinal Study of Ageing

Extent: 7p.The purpose was to examine the relationship between different types of social networks and memory over 15 years of followup in a large cohort of older Australians who were cognitively intact at study baseline. Our specific aims were to investigate whether social networks were associated with memory, determine if different types of social networks had different relationships with memory, and examine if changes in memory over time differed according to types of social networks. We used five waves of data from the Australian Longitudinal Study of Ageing, and followed 706 participants with an average age of 78.6 years (SD 5.7) at baseline. The relationships between five types of social networks and changes in memory were assessed. The results suggested a gradient of effect; participants in the upper tertile of friends or overall social networks had better memory scores than those in the mid tertile, who in turn had better memory scores than participants in the lower tertile. There was evidence of a linear, but not quadratic, effect of time on memory, and an interaction between friends’ social networks and time was apparent. Findings are discussed with respect to mechanisms that might explain the observed relationships between social networks and memory.Lynne C. Giles, Kaarin J. Anstey, Ruth B. Walker and Mary A. Luszc