Work function of a quasicrystal surface: Icosahedral Al–Pd–Mn

The work function of a surface is one of its most basic and influential features. It has long been recognized that work function controls thermionic and field emission. The work function of a solid surface affects charge transfer to or from an adsorbate. It influences the electron tunneling probability between surfaces. It plays a role in quantization of electron states parallel to the surface in metal-supported metallic nanoislands. There is also evidence linking the work function of a metal surface to its friction coefficient

Healthcare and Financial Decision Making and Incident Adverse Cognitive Outcomes among Older Adults

OBJECTIVES To determine if poorer healthcare and financial decision making forecasts adverse cognitive outcomes in old age. Specifically, we hypothesized that poorer decision making would be associated with an increased risk of incident Alzheimer's dementia, an increased risk of incident mild cognitive impairment (MCI), and a more rapid decline in cognition. DESIGN An ongoing prospective observational cohort study of aging (the Rush Memory and Aging Project). SETTING The greater Chicago area. PARTICIPANTS A total of 952 community‐based older adults without dementia at baseline. MEASUREMENTS Participants completed a measure of healthcare and financial decision making at baseline and underwent annual standardized evaluations to track clinical status and cognitive functions (global cognition, episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability). RESULTS During up to 9 years of follow‐up (M  = 5.2 y; standard deviation = 2.7), 156 participants developed Alzheimer's dementia (16.4% of 952), 253 participants developed MCI (33.2% of 760), and each cognitive measure declined (all P s < .001). In Cox proportional hazards models adjusted for age, sex, and education, poorer decision making was associated with an increased risk of incident Alzheimer's dementia (hazard ratio [HR] = 1.17; 95% confidence interval [CI] = 1.10‐1.24; P  < .001) and incident MCI (HR = 1.16; 95% CI = 1.10‐1.22; P  < .001). Further, in linear mixed‐effects models, poorer decision making among those who were initially free of cognitive impairment was associated with a more rapid decline in global cognition and four of five specific cognitive domains (all P s < .05). CONCLUSION Our results suggest that poorer healthcare and financial decision making heralds adverse cognitive outcomes in old age

Harm avoidance is associated with progression of parkinsonism in community-dwelling older adults: a prospective cohort study

BACKGROUND: We tested the hypothesis that harm avoidance, a trait associated with behavioral inhibition, is associated with the rate of change in parkinsonism in older adults. METHODS: At baseline harm avoidance was assessed with a standard self-report instrument in 969 older people without dementia participating in the Rush Memory and Aging Project, a longitudinal community-based cohort study. Parkinsonism was assessed annually with a modified version of the motor section of the Unified Parkinson’s Disease Rating Scale (mUPDRS). RESULTS: Average follow-up was 5 years. A linear mixed-effects model controlling for age, sex and education showed that for an average participant (female, 80 years old at baseline, with 14 years of education and a harm avoidance score of 10), the overall severity of parkinsonism increased by about 0.05 unit/ year (Estimate, 0.054, S.E., 0.007, p <0.001) and that the level of harm avoidance was associated with the progression of parkinsonism (Estimate, 0.004, S.E., 0.001, p <0.001). Thus, for an average participant, every 6 point (~1 SD) increase in harm avoidance score at baseline, the rate of progression of parkinsonism increased about 50% compared to an individual with an average harm avoidance score. This amount of change in parkinsonism over the course of the study was associated with about a 5% increased risk of death. The association between harm avoidance and progression of parkinsonism persisted when controlling for cognitive function, depressive symptoms, loneliness, neuroticism, late-life cognitive, social and physical activities and chronic health conditions. CONCLUSION: A higher level of the harm avoidance trait is associated with a more rapid progression of parkinsonism in older adults

Association of cognition with temporal discounting in community based older persons

Background: The objective of this study was to test the hypothesis that cognitive function is negatively associated with temporal discounting in old age. Methods Participants were 388 community-dwelling older persons without dementia from the Rush Memory and Aging Project, an ongoing longitudinal epidemiologic study of aging in the Chicago metropolitan area. Temporal discounting was measured using standard questions in which participants were asked to choose between an immediate, smaller payment and a delayed, larger one. Cognition was measured using a detailed battery including 19 tests. The association between cognition and temporal discounting was examined via mixed models adjusted for age, sex, education, income, and the number of chronic medical conditions. Results: Descriptive data revealed a consistent pattern whereby older persons with lower cognitive function were more likely to discount greater but delayed rewards compared to those with higher cognitive function. Further, in a mixed effect model adjusted for age, sex, education, income, and chronic medical conditions, global cognitive function was negatively associated with temporal discounting (estimate = −0.45, SE = 0.18, p = 0.015), such that a person with lower cognition exhibited greater discounting. Finally, in subsequent models examining domain specific associations, perceptual speed and visuospatial abilities were associated with temporal discounting, but episodic memory, semantic memory and working memory were not. Conclusion: Among older persons without dementia, a lower level of cognitive function is associated with greater temporal discounting. These findings have implications regarding the ability of older persons to make decisions that involve delayed rewards but maximize well-being.Economic

Progression of Electrocardiographic Abnormalities in Type 1 Diabetes During 16 Years of Follow‐up: The Epidemiology of Diabetes Interventions and Complications (EDIC) Study

Background The electrocardiogram (ECG) is an objective tool for cardiovascular disease (CVD) risk assessment. Methods and Results We evaluated distribution of ECG abnormalities and risk factors for developing new abnormalities in 1314 patients with type 1 diabetes (T1D) from the Epidemiology of Diabetes Interventions and Complications (EDIC) study. Annual ECGs were centrally read. ECG abnormalities were classified as major and minor according to the Minnesota ECG Classification. At EDIC year 1 (baseline), 356 (27.1%) of the participants had at least 1 ECG abnormality (major or minor) whereas 26 (2%) had at least one major abnormality. During 16 years of follow‐up, 1016 (77.3%) participants developed at least 1 new ECG abnormality (major or minor), whereas 172 (13.1%) developed at least 1 new major abnormality. Independent risk factors for developing new major ECG abnormalities were: age, current smoking, increased systolic blood pressure, and higher glycosylated hemoglobin (hazard ratio [HR] [95% CI]: 1.04 [1.02–1.06] per 1‐year increase, 1.75 [1.22–2.53], 1.03 [1.01–1.05] per 1 mm Hg increase, and 1.16 [1.04–1.29] per 10% increase, respectively). Independent risk factors for developing any new ECG abnormalities (major or minor) were age and systolic blood pressure (HR [95% CI]: 1.02 [1.01–1.03] per 1‐year increase and 1.01 [1.00–1.02] per 1 mm Hg increase, respectively). Conclusions New ECG abnormalities commonly occur in the course of T1D, consistent with the recognized increasing risk for CVD as patients age. Advanced age, increased systolic blood pressure, smoking, and higher HbA1c are independent risk factor for developing major ECG abnormalities, which underscores the importance of tight glucose control in T1D in addition to management of common CVD risk factors

Dynamic Regulation of Alternative Splicing by Silencers that Modulate 5′ Splice Site Competition

SummaryAlternative splicing makes a major contribution to proteomic diversity in higher eukaryotes with ∼70% of genes encoding two or more isoforms. In most cases, the molecular mechanisms responsible for splice site choice remain poorly understood. Here, we used a randomization-selection approach in vitro to identify sequence elements that could silence a proximal strong 5′ splice site located downstream of a weakened 5′ splice site. We recovered two exonic and four intronic motifs that effectively silenced the proximal 5′ splice site both in vitro and in vivo. Surprisingly, silencing was only observed in the presence of the competing upstream 5′ splice site. Biochemical evidence strongly suggests that the silencing motifs function by altering the U1 snRNP/5′ splice site complex in a manner that impairs commitment to specific splice site pairing. The data indicate that perturbations of non-rate-limiting step(s) in splicing can lead to dramatic shifts in splice site choice

Progression of Carotid Artery Intima-Media Thickness During 12 Years in the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) Study

OBJECTIVE This study investigated the long-term effects of intensive diabetic treatment on the progression of atherosclerosis, measured as common carotid artery intima-media thickness (IMT). RESEARCH DESIGN AND METHODS A total of 1,116 participants (52% men) in the Epidemiology of Diabetes Interventions and Complications (EDIC) trial, a long-term follow-up of the Diabetes Control and Complications Trial (DCCT), had carotid IMT measurements at EDIC years 1, 6, and 12. Mean age was 46 years, with diabetes duration of 24.5 years at EDIC year 12. Differences in IMT progression between DCCT intensive and conventional treatment groups were examined, controlling for clinical characteristics, IMT reader, and imaging device. RESULTS Common carotid IMT progression from EDIC years 1 to 6 was 0.019 mm less in intensive than in conventional (P < 0.0001), and from years 1 to 12 was 0.014 mm less (P = 0.048); but change from years 6 to 12 was similar (intensive − conventional = 0.005 mm, P = 0.379). Mean A1C levels during DCCT and DCCT/EDIC were strongly associated with progression of IMT, explaining most of the differences in IMT progression between DCCT treatment groups. Albuminuria, older age, male sex, smoking, and higher systolic blood pressure were significant predictors of IMT progression. CONCLUSIONS Intensive treatment slowed IMT progression for 6 years after the end of DCCT but did not affect IMT progression thereafter (6–12 years). A beneficial effect of prior intensive treatment was still evident 13 years after DCCT ended. These differences were attenuated but not negated after adjusting for blood pressure. These results support the early initiation and continued maintenance of intensive diabetes management in type 1 diabetes to retard atherosclerosis

Possible limitations of dolphin echolocation: a simulation study based on a cross-modal matching experiment

© The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wei, C., Hoffmann-Kuhnt, M., Au, W. W. L., Ho, A. Z. H., Matrai, E., Feng, W., Ketten, D. R., & Zhang, Y. Possible limitations of dolphin echolocation: a simulation study based on a cross-modal matching experiment. Scientific Reports, 11(1), (2021): 6689, https://doi.org/10.1038/s41598-021-85063-2.Dolphins use their biosonar to discriminate objects with different features through the returning echoes. Cross-modal matching experiments were conducted with a resident bottlenose dolphin (Tursiops aduncus). Four types of objects composed of different materials (water-filled PVC pipes, air-filled PVC pipes, foam ball arrays, and PVC pipes wrapped in closed-cell foam) were used in the experiments, respectively. The size and position of the objects remained the same in each case. The data collected in the experiment showed that the dolphin’s matching accuracy was significantly different across the cases. To gain insight into the underlying mechanism in the experiments, we used finite element methods to construct two-dimensional target detection models of an echolocating dolphin in the vertical plane, based on computed tomography scan data. The acoustic processes of the click’s interaction with the objects and the surrounding media in the four cases were simulated and compared. The simulation results provide some possible explanations for why the dolphin performed differently when discriminating the objects that only differed in material composition in the previous matching experiments.One of the authors, Wei. C is supported by a Forrest Research Foundation Fellowship. Support for D. Ketten for this effort was provided by the Joint Industry Programme and by the Helmholtz Foundation. This work was also supported by the Hawaii Institute of Marine Biology (HIMB) contribution No. 1630 and School of Ocean and Earth Science and Technology (SOEST) contribution No. 9452