Incorporating Alternative Sources of Reinforcement through Online CRA Goal Setting and the Effect on Substance Use in College Students

Emerging adulthood is a transition period where many college students choose to engage in high-risk substance use (e.g., binge drinking). This choice to misuse substances occurs during a developmental period when students are faced with an increased responsibility to structure and manage their time across multiple personal (and potentially competing) goals. The current study approached the problem of college drinking by using two procedures from the Community Reinforcement Approach (CRA). Rating current happiness and coupling it with goal setting was evaluated as a potential means of increasing substance-free reinforcement that could compete with (i.e., reduce) alcohol use. Males and females ages 18-25 years who consumed alcohol in the last 30 days were randomized to either a control condition (n = 89) or a goal-setting condition (n = 79). Both conditions reported their substance use and levels of happiness at baseline and during a one-month follow up. In the goal-setting condition, the most commonly selected goal was physical exercise. Participants in this condition increased their happiness and reduced their alcohol consumption over the course of the study. Overall, the goal-setting condition reported a greater reduction in alcohol use when compared to the control group. Additionally, this study found that more time spent in academic activities or volunteering/charity work (among the experimental condition) was correlated with lower levels of alcohol use at baseline. An increase in the amount of time spent in academic activities or spiritual activities was correlated with lower levels of alcohol consumption at follow up. This study also evaluated the Pleasant Activities List (PAL), a modern survey instrument that has not yet been used with U.S. college students. It was found that alcohol-related reinforcement was highly correlated with measures of alcohol use. The PAL was also highly correlated with the Adolescent Reinforcement Survey Schedule (ARSS), a survey instrument commonly used with college students in the U.S. Social activities, especially those that involve friends or a potential romantic partner, were found to be highly reinforcing with alcohol while individual activities, such as self-care and physical fitness, were low in alcohol-related reinforcement. The implications of a reinforcement-based approach are discussed

The relation of BDNF VAL66MET polymorphism to neural volume and drinking behavior among adolescents

Brain-Derived Neurotrophic Factor (BDNF) plays an important role in neural plasticity, learning and memory. Due to its relation to neurogenesis, BDNF has been studied with respect to its protective effects against various cognitive dysregulations, including those related to alcohol dependence. Recent evidence suggests that alcohol dependent individuals, in addition to those with a family history of alcoholism, have lower basal levels of BDNF as compared to controls. In adult populations, the Met variant of the Val66Met polymorphism, which results in decreased release of BDNF, has been associated with decreased neural volume as well as increased risk for alcohol problems. Using samples with prolonged alcohol exposure makes it difficult to determine the direction of the relationship between neural volume and drinking behavior. Therefore the current study set out to determine whether a relationship between BDNF, neural volume and drinking behavior could be detected using a sample of adolescents. Since this relationship is well demonstrated using adult samples, it was hypothesized that BDNF genotype would be correlated with drinking behavior among adolescents, and this relationship would be mediated by differences in neural volume. 220 adolescents gave saliva samples, participated in magnetic resonance imaging (MRI), and completed behavioral measures designed to assess drinking behavior. Although BDNF was not correlated with drinking behavior, other interesting relationships were discovered including an inverse relationship between age and cerebral cortex volume, a positive relationship between accumbens volume and drinking, and distinct findings based on gender

Evidence for strong shear velocity reductions and velocity gradients in the lower mantle beneath Africa

We present data which indicate that the broad, low shear velocity anomaly beneath southern Africa is stronger and more extensive than previously thought. Recordings of earthquakes in the southwestern Atlantic Ocean at an array of broadband seismic stations in eastern Africa show anomalously large propagation time delays of the shear phases S, ScS, and SKS which vary rapidly with epicentral distance. By forward modeling, we estimate that the low velocity anomaly extends from the core-mantle boundary about 1500 km up into the mantle and that the average shear velocity within this structure is 3% lower than in standard models such as PREM. Strong velocity contrasts exist at its margins (2% over about 300 km). These seismic characteristic are consistent with recent numerical simulations of lower mantle mega-plume formation

Gravimetrically prepared carbon dioxide standards in support of atmospheric research

We have explored a one-step method for gravimetric preparation of CO2-in-air standards in aluminum cylinders. We consider both adsorption to stainless steel surfaces used in the transfer of highly pure CO2 and adsorption of CO2 to cylinder walls. We demonstrate that CO2-in-air standards can be prepared with relatively low uncertainty (∼&thinsp;0.04&thinsp;%, ∼95&thinsp;% confidence level) by introducing aliquots whose masses are known to high precision and by using well-characterized cylinders. Five gravimetric standards, prepared over the nominal range of 350 to 490&thinsp;µmol mol−1 (parts per million,&thinsp;ppm), showed excellent internal consistency, with residuals from a linear fit equal to 0.05&thinsp;ppm. This work compliments efforts to maintain the World Meteorological Organization, Global Atmosphere Watch, mole fraction scale for carbon dioxide in air, widely used for atmospheric monitoring. This gravimetric technique could be extended to other atmospheric trace gases, depending on the vapor pressure of the gas.</p

Regional Methane Emission Estimation Based on Observed Atmospheric Concentrations (2002-2012)

Methane (CH4) plays important roles in atmospheric chemistry and short-term forcing of climate. A clear understanding of atmospheric CH4’s budget of emissions and losses is required to aid sustainable management of Earth’s future environment. We used an atmospheric chemistry-transport model (JAMSTEC’s ACTM) for simulating atmospheric CH4. A global inverse modeling system has been developed for estimating CH4 emissions from 53 land regions for 2002-2012 using measurements at 39 sites. An ensemble of 7 inversions is performed by varying a priori emissions. Global net CH4 emissions varied between 505-509 and 524-545 Tg yr-1 during 2002-2006 and 2008-2012, respectively (ranges based on 7 inversion cases), with a step like increase in 2007 in agreement with atmospheric measurements. The inversion system did not account for interannual variations in OH radicals reacting with CH4 in the atmosphere. Our results suggest that the recent update of the EDGAR inventory (version 4.2FT2010) overestimated the global total emissions by at least 25 Tg yr-1 in 2010. The increase in CH4 emission since 2004 originated in the tropical and southern hemisphere regions, coinciding with an increase in non-dairy cattle stocks by ~10 % from 2002 (with 1056 million heads) to 2012, leading to ~10 Tg yr-1 increase in emissions from enteric fermentation. All 7 ensemble cases robustly estimated the interannual variations in emissions, but poorly constrained the seasonal cycle amplitude or phase consistently for all regions due to the sparse observational network. Forward simulation results using both a priori and a posteriori emissions are compared with independent aircraft measurements for validation. Based on the results of the comparison, we reject the upper limit (545 Tg yr-1) of global total emissions as 14 Tg yr-1 too high during 2008-2012, which allows us to further conclude that the increase in CH4 emissions over the East Asia (mainly China) region was 7-8 Tg yr-1 between the 2002-2006 and 2008-2012 periods, contrary to 1-17 Tg yr-1 in the a priori emissions

Year-round trace gas measurements in the central Arctic during the MOSAiC expedition

Despite the key role of the Arctic in the global Earth system, year-round in-situ atmospheric composition observations within the Arctic are sparse and mostly rely on measurements at ground-based coastal stations. Measurements of a suite of in-situ trace gases were performed in the central Arctic during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition. These observations give a comprehensive picture of year-round near-surface atmospheric abundances of key greenhouse and trace gases, i.e., carbon dioxide, methane, nitrous oxide, ozone, carbon monoxide, dimethylsulfide, sulfur dioxide, elemental mercury, and selected volatile organic compounds (VOCs). Redundancy in certain measurements supported continuity and permitted cross-evaluation and validation of the data. This paper gives an overview of the trace gas measurements conducted during MOSAiC and highlights the high quality of the monitoring activities. In addition, in the case of redundant measurements, merged datasets are provided and recommended for further use by the scientific community. &nbsp;</p