Effects of Increased Drought in Amazon Forests Under Climate Change: Separating the Roles of Canopy Responses and Soil Moisture

The Amazon forests are one of the largest ecosystem carbon pools on Earth. Although more frequent and prolonged future droughts have been predicted, the impacts have remained largely uncertain, as most land surface models (LSMs) fail to capture the vegetation drought responses. In this study, the ability of the LSM JSBACH to simulate the drought responses of leaf area index (LAI) and leaf litter production in the Amazon forests is evaluated against artificial drought experiments. Based on the evaluation, improvements are implemented, including a dependency of leaf growth on leaf carbon allocation and a better representation of drought-dependent leaf shedding. The modified JSBACH is shown to capture the drought responses at two sites and across different regions of the basin. It is then coupled with an atmospheric model to simulate the carbon and biogeophysical feedbacks of drought under future climate. We separate the drought impacts into (a) the direct effect, resulting from drier soil and stomatal closure, which does not involve a change in canopy structure, and (b) the LAI effect, resulting from leaf shedding and involving canopy response. We show that the latter accounts for 35% of reduced land carbon uptake (9 ± 10 vs. 26 ± 7 g/m2/yr; mean ± 1 sd) and 12% of surface warming (0.09 ± 0.03 vs. 0.7 ± 0.07 K) during the late 21st century. A north-south dipole of precipitation change is found, which is largely attributable to the direct effect. The results highlight the importance of incorporating drought deciduousness of tropical rainforests in LSMs to better simulate land-atmosphere interactions in the future

Sense of Purpose in Life and Five Health Behaviors in Older Adults

Accumulating evidence shows that a higher sense of purpose in life is associated with lower risk of chronic conditions and premature mortality. Health behaviors might partially explain these findings, however, the prospective association between sense of purpose and health behaviors is understudied. We tested whether a higher sense of purpose at baseline was associated with lower likelihood of developing unhealthy behaviors over time. Prospective data were from the Health and Retirement Study, a national sample of U.S. older adults. Our sample included 13,770 adults assessed up to five times across eight years. Among people who met recommended guidelines for a given health behavior outcome at baseline, those in the top versus lowest quartile of purpose in life had 24% lower likelihood of becoming physically inactive (95% CI: 0.68–0.85), 33% lower likelihood of developing sleep problems (95% CI: 0.58–0.79), and 22% lower likelihood of developing unhealthy body mass index (BMI) (95% CI: 0.69–0.87) in sociodemographic-adjusted models. Further there was a marginal reduction in smoking relapse (HR = 0.65, 95% CI: 0.41–1.03) and no association with heavy alcohol use (HR = 1.02, 95% CI: 0.81–1.29). Findings for physical inactivity, sleep problems, and unhealthy BMI remained evident after further adjusting for baseline health status and depression. Our results, suggest that a sense of purpose in life might emerge (with further research) as a valuable target to consider for interventions aimed at helping older adults maintain some health behaviors

Sirtuin1 protects endothelial Caveolin-1 expression and preserves endothelial function via suppressing miR-204 and endoplasmic reticulum stress.

Sirtuin1 (Sirt1) is a class III histone deacetylase that regulates a variety of physiological processes, including endothelial function. Caveolin1 (Cav1) is also an important determinant of endothelial function. We asked if Sirt1 governs endothelial Cav1 and endothelial function by regulating miR-204 expression and endoplasmic reticulum (ER) stress. Knockdown of Sirt1 in endothelial cells, and in vivo deletion of endothelial Sirt1, induced endothelial ER stress and miR-204 expression, reduced Cav1, and impaired endothelium-dependent vasorelaxation. All of these effects were reversed by a miR-204 inhibitor (miR-204 I) or with overexpression of Cav1. A miR-204 mimic (miR-204 M) decreased Cav1 in endothelial cells. In addition, high-fat diet (HFD) feeding induced vascular miR-204 and reduced endothelial Cav1. MiR-204-I protected against HFD-induced downregulation of endothelial Cav1. Moreover, pharmacologic induction of ER stress with tunicamycin downregulated endothelial Cav1 and impaired endothelium-dependent vasorelaxation that was rescued by overexpressing Cav1. In conclusion, Sirt1 preserves Cav1-dependent endothelial function by mitigating miR-204-mediated vascular ER stress

Hyperbolic Kac-Moody Algebra from Intersecting p-branes

A subclass of recently discovered class of solutions in multidimensional gravity with intersecting p-branes related to Lie algebras and governed by a set of harmonic functions is considered. This subclass in case of three Euclidean p-branes (one electric and two magnetic) contains a cosmological-type solution (in 11-dimensional model with two 4-forms) related to hyperbolic Kac-Moody algebra ${\cal F}_3$ (of rank 3). This solution describes the non-Kasner power-law inflation.Comment: 15 pages, Latex. A talk presented at the Second Winter School on Branes, Fields and Math. Phys. (Seoul, Korea). Corrected version. Journ. ref.: J. Math. Phys., 40, (1999) 4072-4083; Corrigenda to appea

Longitudinal Associations Between Psychological Well-Being and the Consumption of Fruits and Vegetables

Background: Psychological well-being is associated with longevity and reduced risk of disease, but possible mechanisms are understudied. Health behaviors like eating fruits and vegetables may link psychological well-being with better health; however, most evidence is cross-sectional. Purpose: This study investigated psychological well-being’s longitudinal association with fruit and vegetable consumption across as many as 7 years. Method: Participants were 6,565 older adults from the English Longitudinal Study of Ageing, which includes men and women aged 50 years or older. Psychological well-being was assessed with 17 items from the Control, Autonomy, Satisfaction, Pleasure Scale. Fruit and vegetable consumption was initially assessed during 2006–2007 and then approximately every 2 years through 2012–2013. Covariates included sociodemographic factors, health status, and other health behaviors. Results: Mixed linear models showed that higher baseline levels of psychological well-being were associated with more fruit and vegetable consumption at baseline (β = 0.05, 95% confidence interval [CI] [0.02, 0.08]) and that fruit and vegetable consumption declined across time (β = −0.01, 95% CI [−0.02, −0.004]). Psychological well-being interacted significantly with time such that individuals with higher baseline psychological well-being had slower declines in fruit and vegetable consumption (β = 0.01, 95% CI [0.01, 0.02]). Among individuals who initially met recommendations to consume 5 or more servings of fruits and vegetables (N = 1,719), higher baseline psychological well-being was associated with 11% reduced risk of falling below recommended levels during follow-up (hazard ratio = 0.89, 95% CI [0.83, 0.95]). Conclusions: Findings suggest that psychological well-being may be a precursor to healthy behaviors such as eating a diet rich in fruits and vegetables. (PsycInfo Database Record (c) 2020 APA, all rights reserved

A Pilot Randomized Controlled Trial of a Videoconferencing Smoking Cessation Intervention for Korean American Women: Preliminary Findings

Introduction: Korean American women prefer online or telephone smoking cessation interventions that can be remotely accessed from home. However, these interventions have been found ineffective for the group. Methods: This study is a pilot clinical trial testing the feasibility and acceptability of a videoconferencing smoking cessation intervention for Korean American women and compared its preliminary efficacy with a telephone-based smoking cessation intervention. Korean women in the United States were recruited nationwide and randomly assigned at a ratio of 1:1 to either a video arm or a telephone arm. Participants in both arms received eight 30-minute weekly individualized counseling sessions of a culturally adapted smoking cessation intervention and nicotine patches for 8 weeks. They were followed up at post-quit 1, 2, and 3 months. Results: A total of 168 Korean Americans were assessed for eligibility, 77 were determined to eligible and 49 participated in the study. The videoconferencing intervention was acceptable and feasible for women under 50 years, whereas it was not for older women. The videoconferencing intervention produced abstinence rates of 67% at post-quit 1 month and 42% at post-quit 3 months based on self-report. The rate at post-quit 3 months dropped to 33% when those women whose abstinence could not be validated with salivary cotinine tests were treated as smoking. Abstinence rates in the telephone arm did not differ from those in the video arm. Conclusion: Findings suggest that videoconferencing smoking cessation intervention may be feasible and acceptable for Korean American women under 50 years. However, for older Korean American women, the intervention may not be feasible and telephone-based intervention seems to be just as effective if smoking cessation intervention components are adapted at a deep structural level of Korean culture by integrating its core cultural values and addressing psychosocial, social and environmental forces affecting the behavior

Regulation of stanniocalcin-1 secretion by BeWo cells and first trimester human placental tissue from normal pregnancies and those at increased risk of developing preeclampsia.

Stanniocalcin-1 (STC-1) is a multi-functional glycosylated peptide present in the plasma of healthy women postpartum and increased further in pregnancies complicated by preeclampsia. Although the STC-1 gene is expressed by the placenta what regulates its secretion and from which cells at the feto-maternal interface is unknown. Here, we demonstrate for the first time that the syncytiotrophoblast and cytotrophoblast are a major site of STC-1 protein expression in first trimester placental tissue. Further, in response to low oxygen, first trimester chorionic villous tissue from pregnancies at increased risk of developing preeclampsia secreted significantly more STC-1 than normal tissue under the same conditions. Using the human trophoblast cell line BeWo we have shown that low oxygen increased the secretion of STC-1 but it required co-stimulation with the Adenosine-3', 5'-cyclic monophosphate (cAMP) analogue, 8-Bromo adenosine-3', 5'-cyclic monophosphate cAMP (8 Br-cAMP) to reach significance. Inhibition of Hypoxia inducible factor 2α (HIF-2α) and the Phosphatidylinositol-3 kinase (PI3 -Kinase)/AKT/Serum and glucocorticoid-induced kinase-1(SGK-1) pathway resulted in significant inhibition of STC-1 secretion. As both low oxygen and cAMP are known to play a central role in placental function, their regulation of STC-1 points to a potentially important role in the maintenance of a normal healthy pregnancy and we would hypothesize that it may act to protect against prolonged placental hypoxia seen in preeclampsia

Intrinsic Absorption in the Spectrum of NGC 7469: Simultaneous Chandra, FUSE, and STIS Observations

We present simultaneous X-ray, far-ultraviolet, and near-ultraviolet spectra of the Seyfert 1 galaxy NGC 7469 obtained with the Chandra X-Ray Observatory, the Far Ultraviolet Spectroscopic Explorer, and the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. Previous non-simultaneous observations of this galaxy found two distinct UV absorption components, at -560 and -1900 km/s, with the former as the likely counterpart of the X-ray absorber. We confirm these two absorption components in our new UV observations, in which we detect prominent O VI, Ly alpha, N V, and C IV absorption. In our Chandra spectrum we detect O VIII emission, but no significant O VIII or O VII absorption. We also detect a prominent Fe K alpha emission line in the Chandra spectrum, as well as absorption due to hydrogen-like and helium-like neon, magnesium, and silicon at velocities consistent with the -560 km/s UV absorber. The FUSE and STIS data reveal that the H I and C IV column densities in this UV- and X-ray- absorbing component have increased over time, as the UV continuum flux decreased. We use measured H I, N V, C IV, and O VI column densities to model the photoionization state of both absorbers self-consistently. We confirm the general physical picture of the outflow in which the low velocity component is a highly ionized, high density absorber with a total column density of 10^20 cm^-2, located near the broad emission line region, although due to measurable columns of N V and C IV, we assign it a somewhat smaller ionization parameter than found previously, U~1. The high velocity UV component is of lower density, log N=18.6, and likely resides farther from the central engine as we find its ionization parameter to be U=0.08.Comment: Minor correction to abstract; STScI eprint #1683; 50 pages, incl. 19 figures, 4 tables; Accepted to Ap

State Medical Marijuana Laws and the Prevalence of Opioids Detected Among Fatally Injured Drivers

Objectives. To assess the association between medical marijuana laws (MMLs) and the odds of a positive opioid test, an indicator for prior use. Methods. We analyzed 1999–2013 Fatality Analysis Reporting System (FARS) data from 18 states that tested for alcohol and other drugs in at least 80% of drivers who died within 1 hour of crashing (n = 68 394). Within-state and between-state comparisons assessed opioid positivity among drivers crashing in states with an operational MML (i.e., allowances for home cultivation or active dispensaries) versus drivers crashing in states before a future MML was operational. Results. State-specific estimates indicated a reduction in opioid positivity for most states after implementation of an operational MML, although none of these estimates were significant. When we combined states, we observed no significant overall association (odds ratio [OR] = 0.79; 95% confidence interval [CI] = 0.61, 1.03). However, age-stratified analyses indicated a significant reduction in opioid positivity for drivers aged 21 to 40 years (OR = 0.50; 95% CI = 0.37, 0.67; interaction P < .001). Conclusions. Operational MMLs are associated with reductions in opioid positivity among 21- to 40-year-old fatally injured drivers and may reduce opioid use and overdose