Anthropogenic climate change in the western U.S. involves increasing temperatures, decreasing water availability and increasing frequency of extreme weather events. Predicting how subalpine forests will respond to climate change is complicated by variation in intraspecific responses. To address the question of whether subalpine tree populations will be able to tolerate future climatic conditions within their current distribution, I compared the physiological, phenological and morphological response of seedlings of two limber pine (Pinus flexilis James) mitochondrial haplotypes (narrow and wide-ranging) to simulated climate change. I conducted a 15-week growth chamber experiment on seedlings under low light conditions and two temperature treatments: ambient (recent climate conditions) and heated (ambient +5°C). I recorded the timing of developmental stages and measured seedling net photosynthetic and dark respiration rates, total biomass, root to shoot mass and length, specific leaf area (SLA) and specific root length (SRL). I found that the ambient chamber had greater average rates of net photosynthesis and dark respiration. Between haplotypes, there was a marginally significant difference in net photosynthesis and a significant difference in dark respiration. There were significant morphological differences between the haplotypes and chambers in root to shoot mass and SLA. Seedlings in the heated chamber germinated, on average, two weeks earlier than in the heated chamber and experienced a five-fold increase in mortality rate. The results of this experiment suggests that limber pine seedlings growing in the shade in a 5°C warmer climate will suffer near zero carbon balance, increased mortality, and will experience a longer growing season.

Background: Drinking among older adults might increase in the future due to relatively high rates of alcohol use in the "baby boomer" cohort and the rise in the proportion of older adults in the USA. Little is known, however, about potential moderation and mediation mechanisms determining risk or how these processes vary by gender or race/ethnicity. Guided by a cumulative inequality framework, three nationally representative analyses were conducted to help untangle the complicated relationships between risk factors for drinking and drinking related behaviors in older age, particularly for older women and older adults of color.

Methods: Logistic regression and path analysis models were used to examine drinking and related behaviors among adults aged 60 or older, using samples from the 2002-2010 National Health and Nutrition Epidemiologic Survey (NHANES).

Results: Alcohol use in older adulthood may be even more problematic than previously thought due to the concurrent use of alcohol-interactive prescription drugs (AIPD), particularly for Mexican American men and Black women. Although no mediation effects were found, gender and race/ethnicity significantly modified several relationships between risk factors and drinking in older age. Older men who are impaired by depressive symptoms are at lower risk of heavy episodic drinking, while older women who are impaired by depressive symptoms are at higher risk of heavy episodic drinking. Gender and race/ethnicity also moderate the relationship between physical health and at-risk or heavy episodic drinking in old age, with highest risk for Mexican American men and Black older adults in poor health.

Discussion: Drinking in older age is a not a monolithic behavior, instead there is considerable variation in which factors increase risk. Inconsistencies in the literature investigating drinking in older age are not just due to lack of research, but also to lack of research recognizing these important variations. Research efforts and social work practice with older adults must account for gender and racial/ethnic differences in order to help improve understanding, strengthen assessment efforts, and optimize treatment opportunities. Additionally, it is important to consider the role of AIPD use in older age drinking, as use is highly prevalent and could compound negative outcomes of a social problem poised to become a major public health concern in the 21st century.