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We examine whether cigarettes serve as substitutes for electronic nicotine delivery systems (ENDS) among ENDS users and demonstrate methodological extensions of data from a cross‐price purchase task to inform policies and interventions. During a clinical laboratory study, n = 19 exclusive ENDS users and n = 17 dual cigarette/ENDS users completed a cross‐price purchase task with cigarettes available at a fixed price while prices of own‐brand ENDS increased. We estimated cross‐price elasticity using linear models to examine substitutability. We defined five additional outcomes: nonzero cross‐price intensity (purchasing cigarettes if ENDS were free), constant null demand (not purchasing cigarettes at any ENDS price), cross‐product crossover point (first price where participants purchased more cigarettes than ENDS), dual‐demand score (percentage of prices where both products were purchased), and dual‐use break point (minimum relative price to force complete substitution). The cross‐price elasticity results indicated that cigarettes could serve as substitutes for ENDS among ENDS users on average, but this average effect masked substantial heterogeneity in profiles of demand (here, a measure of the drug's reinforcement potential). Policies and regulations that increase ENDS prices appear unlikely to steer most exclusive ENDS users toward cigarette use, as most would not purchase cigarettes at any ENDS price, but they could prompt some dual users to substitute cigarettes completely while others remain dual users. This heterogeneity in consumer responses suggests additional indices of cross‐product demand are useful to characterize the anticipated and unanticipated effects of tobacco price policies more fully. [ABSTRACT FROM AUTHOR]

Background: Regulatory flexibility (RF) involves three distinct components of self‐regulation: context sensitivity, repertoire, and feedback responsiveness. Subgroups based on differences in RF have been identified in a general sample and are differentially associated with symptoms of anxiety and depression. However, potential RF profiles have not been examined in individuals with substance use disorders. This study examined RF subtypes in individuals with alcohol use disorder (AUD) and their associations with psychosocial outcomes (i.e., depression, anxiety, and stress) and delay discounting (a core feature of addiction). Methods: Individuals (n = 200) with an Alcohol Use Disorders Identification Test score of >16 (mean = 24.12 (±6.92)) were recruited from Amazon Mechanical Turk (mean = 37.26 years old (±11.41); 94 (47%) women). Participants completed the Context Sensitivity Index, the Flexible Regulation of Emotional Expression Scale, and the Coping Flexibility Scale to assess RF. Participants also completed an Adjusting Amount Delay Discounting Task and the Depression, Anxiety, and Stress Scale (DASS‐21). Latent profile analyses (LPA) were used to identify patterns in RF deficits. Kruskal–Wallis and Dunn's tests were performed to examine differences in discounting rates and symptoms of depression, anxiety, and stress across RF profiles. Results: The LPA revealed a 2‐profile characterization, including (1) context sensitive regulators (CSR; n = 39) and (2) moderate flexibility regulators (MFR; n = 161). CSR demonstrated significantly lower symptoms of depression (p = 0.004), anxiety (p < 0.001), and stress (p < 0.001) than MFR. CSR also displayed significantly lower AUDIT scores (p = 0.031). Conclusions: Findings illustrate that among individuals with moderate–severe AUD, those high in context sensitivity coupled with moderate abilities in repertoire and feedback responsiveness have fewer symptoms of depression, anxiety, and stress. Together, context sensitivity may be an important and protective component of RF among individuals with AUD. [ABSTRACT FROM AUTHOR]

Objective: Ultrasound (US) and computed tomography (CT) are commonly used in the diagnosis of pediatric neck abscesses. The objective of this study is to determine the sensitivity and specificity of US and CT in the diagnosis of pediatric lateral neck abscesses, with a secondary objective of evaluating the association of specific clinical features with a positive US or CT scan. Study Design: Retrospective review of pediatric patients admitted to a tertiary care center from January 1, 2011, to December 31, 2020, with neck abscesses. Setting: Tertiary care center. Methods: The sensitivity and specificity of US and CT were calculated by comparing imaging performed within 24 h of incision and drainage (I&D). Multiple regression was used to evaluate the association of clinical features with a true positive US or CT. Results: There were 171 patients included in this study, with a median age of 1.5 years (interquartile range [IQR]: 1‐5 years). I&D was done in 156 patients (91.2%), while 15 (8.8%) were treated with antibiotics. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of US were 69.5%, 80%, 96.6%, and 24.2%. The sensitivity, specificity, PPV, and NPV of neck CT were 95.5%, 80%, 95.5%, and 57.1%. Length of symptoms, skin erythema, and fluctuance were not significantly associated with a positive US (F(3, 82) = 0.24, p =.9, R2 = 0.01) or CT scan (F(3, 30) = 0.84, p =.5, R2 = 0.08). Conclusion: Neck US has a low sensitivity for diagnosing pediatric neck abscesses, when compared to CT, but remains a useful initial investigation given its high PPV. Clinicians should have a low threshold for pursuing CT if there is a high suspicion of abscess formation. Level of Evidence: Level 4. [ABSTRACT FROM AUTHOR]

Background and Aims: Limited information exists regarding individual subgroups of recovery from opioid use disorder (OUD) following treatment and how these subgroups may relate to recovery trajectories. We used multi‐dimensional criteria to identify OUD recovery subgroups and longitudinal transitions across subgroups. Design, Setting and Participants: In a national longitudinal observational study in the United States, individuals who previously participated in a clinical trial for subcutaneous buprenorphine injections for treatment of OUD were enrolled and followed for an average of 4.2 years after participation in the clinical trial. Measurements: We identified recovery subgroups based on psychosocial outcomes including depression, opioid withdrawal and pain. We compared opioid use, treatment utilization and quality of life among these subgroups. Findings Three dimensions of the recovery process were identified: depression, opioid withdrawal and pain. Using these three dimensions, participants were classified into four recovery subgroups: high‐functioning (minimal depression, mild withdrawal and no/mild pain), pain/physical health (minimal depression, mild withdrawal and moderate pain), depression (moderate depression, mild withdrawal and mild/moderate pain) and low‐functioning (moderate/severe withdrawal, moderate depression and moderate/severe pain). Significant differences among subgroups were observed for DSM‐5 criteria (P < 0.001) and remission status (P < 0.001), as well as with opioid use (P < 0.001), treatment utilization (P < 0.001) and quality of life domains (physical health, psychological, environment and social relationships; Ps < 0.001, Cohen's fs ≥ 0.62). Recovery subgroup assignments were dynamic, with individuals transitioning across subgroups during the observational period. Moreover, the initial recovery subgroup assignment was minimally predictive of long‐term outcomes. Conclusions: There appear to be four distinct subgroups among individuals in recovery from OUD. Recovery subgroup assignments are dynamic and predictive of contemporaneous, but not long‐term, substance use, substance use treatment utilization or quality of life outcomes. [ABSTRACT FROM AUTHOR]

Background: Delay discounting (DD), the decrease in reward valuation as a function of delay to receipt, is a key process undergirding alcohol use. Narrative interventions, including episodic future thinking (EFT), have decreased delay discounting and demand for alcohol. Rate dependence, the relationship between a baseline rate and change in that rate after an intervention, has been evidenced as a marker of efficacious substance use treatment, but whether narrative interventions have rate‐dependent effects needs to be better understood. We investigated the effects of narrative interventions on delay discounting and hypothetical demand for alcohol in this longitudinal, online study. Methods: Individuals (n = 696) reporting high‐ or low‐risk alcohol use were recruited for a longitudinal 3‐week survey via Amazon Mechanical Turk. Delay discounting and alcohol demand breakpoint were assessed at baseline. Individuals returned at weeks 2 and 3 and were randomized into the EFT or scarcity narrative interventions and again completed the delay discounting tasks and alcohol breakpoint task. Oldham's correlation was used to explore the rate‐dependent effects of narrative interventions. Study attrition as a function of delay discounting was assessed. Results: Episodic future thinking significantly decreased, while scarcity significantly increased delay discounting relative to baseline. No effects of EFT or scarcity on the alcohol demand breakpoint were observed. Significant rate‐dependent effects were observed for both narrative intervention types. Higher delay discounting rates were associated with a greater likelihood of attrition from the study. Conclusion: The evidence of a rate‐dependent effect of EFT on delay discounting rates offers a more nuanced, mechanistic understanding of this novel therapeutic intervention and can allow more precise treatment targeting by demonstrating who is likely to receive the most benefit from it. [ABSTRACT FROM AUTHOR]

Individual participant data meta‐analysis is a frequently used method to combine and contrast data from multiple independent studies. Bayesian hierarchical models are increasingly used to appropriately take into account potential heterogeneity between studies. In this paper, we propose a Bayesian hierarchical model for individual participant data generated from the Cigarette Purchase Task (CPT). Data from the CPT details how demand for cigarettes varies as a function of price, which is usually described as an exponential demand curve. As opposed to the conventional random‐effects meta‐analysis methods, Bayesian hierarchical models are able to estimate both the study‐specific and population‐level parameters simultaneously without relying on the normality assumptions. We applied the proposed model to a meta‐analysis with baseline CPT data from six studies and compared the results from the proposed model and a two‐step conventional random‐effects meta‐analysis approach. We conducted extensive simulation studies to investigate the performance of the proposed approach and discussed the benefits of using the Bayesian hierarchical model for individual participant data meta‐analysis of demand curves. [ABSTRACT FROM AUTHOR]

Background: The life‐history theory is a well‐established framework that predicts behaviors and explains how and why organisms allocate effort and resources to different life goals. Delay discounting (DD) is associated with risky behaviors and has been suggested as a candidate behavioral marker of addiction. Thus, we investigated the relationship between DD, life‐history strategies, and engagement in risky behaviors among individuals in recovery from alcohol use disorder (AUD). Methods: Data from 110 individuals in recovery from addiction from The International Quit & Recovery Registry, an ongoing online registry designed to understand recovery phenotype, were included in the analysis. The association between life‐history strategies, DD, engagement in risky behaviors, and remission status were assessed. Results: Life‐history strategy scores were significantly associated with DD rates and finance, health, and personal development behaviors after controlling for age, sex, race, ethnicity, years of education, marital status, smoking status, and history of other substance use. Remission status was significantly associated with life‐history strategy, DD, drug use, fitness, health, and safe driving after controlling for age, sex, race, years of education, marital status, and smoking status. In addition, a mediation analysis using Hayes' methods revealed that the discounting rates partially mediated the association between remission status and life‐history strategy scores. Conclusions: Life‐history strategies and remission status are both significantly associated with DD and various health and finance behaviors among individuals in recovery from AUD. This finding supports the characterizations of DD as a candidate behavioral marker of addiction that could help differentiate subgroups needing special attention or specific interventions to improve the outcomes of their recovery. Future longitudinal studies are warranted to understand the relationships between changes in life‐history strategies, DD, maladaptive health behaviors, and remission status over time. [ABSTRACT FROM AUTHOR]

Summary: The last decade has led to major shifts in opinions on the use of hydroxyethyl starch (HES) solutions in fluid therapy, specifically in human patients with sepsis. The majority of evidence documenting adverse effects of HES solutions on coagulation and renal health come from studies in people. However, these findings have led to investigation into the safety of HES solutions in veterinary species. While there are now studies investigating the effects of HES solutions on coagulation and renal health in dogs, cats and horses, information regarding long‐term follow‐up, clinical significance of these changes and use of these solutions in critically ill animals is still lacking. The information presented here serves to review the physiology of oncotic pressure and the rationale behind colloid use, specifically HES solutions. Additionally, the foundation of arguments against the use of HES and the available literature regarding HES use in animals will be summarised. [ABSTRACT FROM AUTHOR]

Background: Substance use recovery is a dynamic process. Relapse, often part of the recovery process, is a persistent problem for individuals seeking freedom from their harmful substance use and has become a focus of research on the improvement of recovery outcomes. Delay discounting is associated with substance use disorder severity, both its negative outcomes and the propensity to relapse. However, the association between delay discounting and perceived risk of relapse as measured by the Alcohol Warning of Relapse Questionnaire has not previously been examined in a population of individuals in long‐term recovery from substance misuse. Methods: In this study, using data collected from the International Quit and Recovery Registry, we investigated the association between delay discounting, self‐reported time in recovery, and perceived risk of relapse. Data from 193 individuals self‐reporting to be in recovery from harmful substance use were included in the study. Results: Delay discounting rates were significantly negatively associated with length of recovery (p = 0.036) and positively with perceived risk of relapse (p = 0.027) even after controlling for age, gender, education, marital status, ethnicity, race, primary substance, and length in the registry. Moreover, a mediation analysis using Hayes' methods revealed that the association between the length of recovery and perceived relapse risk was partially mediated by delay discounting, accounting for 21.2% of the effect. Conclusions: Our finding supports previous characterizations of delay discounting as a candidate behavioral marker of substance misuse and may help to identify individuals at higher perceived risk of relapse in an extended recovery population. [ABSTRACT FROM AUTHOR]

Background: No clear consensus exists as to whether neurodevelopmental abnormalities among substance users reflect predisposing neural risk factors, neurotoxic effects of substances, or both. Using a longitudinal design, we examined developmental patterns of the bidirectional links between neural mechanisms and substance use throughout adolescence. Method: 167 adolescents (aged 13–14 years at Time 1, 53% male) were assessed annually four times. Risk‐related neural processing was assessed by blood‐oxygen‐level‐dependent responses in the insula during a lottery choice task, cognitive control by behavioral performance during the Multi‐Source Interference Task, and substance use by adolescents' self‐reported cigarette, alcohol, and marijuana use. Results: Latent change score modeling indicated that greater substance use predicted increased insula activation during risk processing, but the effects of insula activation on changes in substance use were not significant. The coupling effect from substance use to insula activation was particularly strong for adolescents with low cognitive control, which supports the theorized moderating role of cognitive control. Conclusions: Our results elucidate how substance use may alter brain development to be biased toward maladaptive decision‐making, particularly among adolescents with poor cognitive control. Furthermore, the current findings underscore that cognitive control may be an important target in the prevention and treatment of adolescent substance use given its moderating role in the neuroadaptive effects of substance use on brain development. [ABSTRACT FROM AUTHOR]

Weathering is a foundational process in most Earth systems, but there has been a lack of data directly quantifying what influences mechanical weathering. Here we use multiple years of in situ field data, "listening" to acoustic emissions of naturally cracking rocks, to test a hypothesized link between climate and subcritical crack‐tip processes (i.e., the bond‐breaking mechanism thought to embody most mechanical weathering). Our results challenge the assumption of a singular dependence of mechanical weathering on stresses. We find that mechanical weathering rates exponentially increase as functions of atmospheric vapor pressure (VP), temperature, and relative humidity, even when controlling for stress‐loading. VP exerts the most pronounced influence on the observed mechanical weathering rates. Put in the context of global climate change, our results underscore the potential for climate‐dependent subcritical crack‐tip processes to influence all weathering‐allied problems including the long‐term stabilization of the climate by weathering‐carbon‐cycle feedbacks. Plain Language Summary: Weathering refers to the mechanisms by which rocks physically and chemically break down into soil, sediment, and dissolved molecules. Chemical weathering rates are frequently inferred to be strongly coupled to climate, because chemical reactions depend on factors like moisture and temperature. In past studies, climate has been connected to physical weathering only through its influence on stress‐inducing processes like freezing or temperature cycling. In this study, we use field observations of the sounds that natural rock cracking makes and find that cracking accelerates in warmer, wetter conditions, even when controlling for stresses. Thus, this study provides field data to support a climatic influence on weathering via a pathway—molecular bond‐breaking at crack‐tips—that is additional to, and distinct from, how climate may influence stresses or chemical weathering. Accordingly, any system connected to weathering, such as Earth's carbon cycle, surface erosion, or biosphere, could be impacted by this additional process of accelerated rock breakdown during warmer and wetter climates, such as those predicted under modern global warming trends. Key Points: After controlling for stress‐loading, mechanical weathering rates—measured in situ—still strongly correlate with moisture and temperatureVapor pressure's influence on crack‐tip subcritical cracking processes appears to govern observed trends, independent of stress magnitudeRecognizing this novel facet of weathering's climate‐dependence will enhance understanding of all climate‐dependent systems like the carbon cycle and landscape evolution [ABSTRACT FROM AUTHOR]

Aims: Amazon Mechanical Turk (MTurk) provides a crowdsourcing platform for the engagement of potential research participants with data collection instruments. This review (1) provides an introduction to the mechanics and validity of MTurk research; (2) gives examples of MTurk research; and (3) discusses current limitations and best practices in MTurk research. Methods: We review four use cases of MTurk for research relevant to addictions: (1) the development of novel measures, (2) testing interventions, (3) the collection of longitudinal use data to determine the feasibility of longer‐term studies of substance use and (4) the completion of large batteries of assessments to characterize the relationships between measured constructs. We review concerns with the platform, ways of mitigating these and important information to include when presenting findings. Results: MTurk has proved to be a useful source of data for behavioral science more broadly, with specific applications to addiction science. However, it is still not appropriate for all use cases, such as population‐level inference. To live up to the potential of highly transparent, reproducible science from MTurk, researchers should clearly report inclusion/exclusion criteria, data quality checks and reasons for excluding collected data, how and when data were collected and both targeted and actual participant compensation. Conclusions: Although on‐line survey research is not a substitute for random sampling or clinical recruitment, the Mechanical Turk community of both participants and researchers has developed multiple tools to promote data quality, fairness and rigor. Overall, Mechanical Turk has provided a useful source of convenience samples despite its limitations and has demonstrated utility in the engagement of relevant groups for addiction science. [ABSTRACT FROM AUTHOR]

The Space Ionizing Radiation Environment and Effects (SIRE2) toolkit has been developed to update and extend the tools used by the space and radiation effects community. It includes new environment models, the capability to examine how the environment changes along satellite and other trajectories and batch processing capabilities for both environments and radiation effects on electronics. An overview of the capabilities in the SIRE2 Toolkit is provided, and examples of applying SIRE2 to satellite orbits and arbitrary trajectories are given. Key Points: The calculation options include legacy models, the latest models, and batch calculations of space radiation environments and radiation effectsThe tools allow space radiation environment calculations on segments of orbits and on arbitrary spacecraft trajectoriesSIRE2 provides a new probabilistic model for solar energetic particle peak flux [ABSTRACT FROM AUTHOR]

The quantification of percolation processes and deep drainage rates in cracking clays is challenging due to the existence of multiple flow pathways, including desiccation crack networks, and the effect of variability in antecedent soil moisture and rain event properties. While most previous research on this topic focuses on long‐term average rates, this study focusses on inter‐event dynamics. The study uses data from soil moisture sensors distributed vertically down 4 m profiles of Vertosol and Chromosol soils across 13 sites over an area of approximately 20 km2. The objectives were to estimate the temporal and spatial variability of deep drainage rates and to investigate the effect of antecedent soil moisture conditions and rain event properties on deep drainage rates and percolation dynamics. 35 deep drainage events over a 40‐month period contributed 78 % of the total deep drainage of 254 mm at 4 m depth. Average deep drainage estimates were about 15 % (ranging from 0 – 80 % between sites) of total rainfall and irrigation in the Vertosol and 8% (0 – 24 %) in the Chromosol. The event water travel times at 4 m depth were 0.25 – 38 hr and 14 – 39 hr in the Vertosol and Chromosol respectively. The event deep drainage rates averaged across sites were associated with event rainfall volumes (linear regression R2 = 0.40), with the effect of antecedent conditions evident only when looking at inter‐site differences. The percolation response time was strongly associated with higher rainfall intensities (R2 = 0.33) with no evidence from the linear regression of an antecedent moisture effect. [ABSTRACT FROM AUTHOR]

The Reinforcer Pathology theory proposes conditions under which drugs emerge as excessively preferred reinforcers compared to other available reinforcers among drug users. The theory highlights 2 key variables as important determinants of drug preference: (a) excessive preference for immediate rewards (high discounting of future rewards); and (b) excessive valuation for addictive reinforcers (e.g., drugs). Two iterations of the Reinforcer Pathology theory exist with the latest iteration (i.e., Reinforcer Pathology 2.0) specifying that the temporal window of reinforcer integration (measured by delay discounting) is a determinant of reinforcer value. The 2 iterations of the Reinforcer Pathology theory are described. A novel insight and understanding of abstinence and relapse from a Reinforcer Pathology perspective, limitations, and future directions are discussed. The Reinforcer Pathology theory continues the long‐standing efforts to scientifically understand and better define novel concepts and methods to further translational research and improve treatment outcomes. Exploring the complementary relation between the Reinforcer Pathology perspective and other current approaches could have a valuable effect. [ABSTRACT FROM AUTHOR]

Background and Aims: Government regulations of nicotine vaping products (NVP) have evolved rapidly during the past decade. The impact of NVP regulatory environment and vaping on cigarette demand is unknown. The current study aims to investigate whether or not respondents' reported cigarette demand, as measured by a hypothetical cigarette purchase task, varies with (1) smoking status, (2) vaping status or (3) NVP regulatory environment (country used as proxy). Design Cross‐sectional survey data from wave 1 of the International Tobacco Control (ITC) Four Country Smoking and Vaping (4CV) Survey (2016). Setting: Australia, Canada, England and the United States. Participants: A total of 10 316 adult smokers. Measurements A hypothetical purchase task asked smokers to estimate how many cigarettes they would purchase for consumption in a single day across multiple cigarette prices. Responses were used to derive measures of cigarette demand. Overall sensitivity of cigarette consumption to price increases was quantified to index cigarette demand elasticity, whereas estimated consumption when cigarettes are free was used to index cigarette demand intensity. Findings A majority of the non‐daily smokers had previously smoked daily (72.3%); daily vapers were more likely to be former daily smokers (89.9%) compared to non‐daily vapers (70.1%) and non‐vapers (69.2%) (P < 0.001). The smoking status × vaping status interaction was significant for cigarette demand intensity (F = 4.93; P = 0.007) and elasticity (F = 7.30; P = 0.001): among non‐daily smokers, vapers reported greater intensity but lower elasticity (i.e. greater demand) relative to non‐vapers (Ps < 0.05). Among daily smokers, daily vapers reported greater intensity relative to non‐vapers (P = 0.005), but vaping status did not impact elasticity (Ps > 0.38). Intensity was higher in Australia compared with all other countries (Ps < 0.001), but elasticity did not vary by country (F = 2.15; P = 0.09). Conclusions: In a hypothetical purchase task, non‐daily smokers showed lower price elasticity if they used e‐cigarettes than if they did not, while there was no clear difference in elasticity between e‐cigarette users and non‐users among daily smokers or according to regulatory environment of their country with regard to e‐cigarettes. [ABSTRACT FROM AUTHOR]

Two studies examined whether episodic future thinking (EFT; pre‐experiencing future events) reduces discounting of future rewards (DD). No studies have investigated whether process simulations (i.e., simulating the process of executing a future event) amplify EFT's reduction of DD. Study 1 examined the effect of incorporating process simulations into EFT (N = 42, Mage = 43.27; 91% female, family income = $75,976) using a 2 × 2 factorial design with type of episodic thinking (process, nonprocess/general) and temporal perspective (EFT, episodic recent thinking) as between‐subjects factors. Study 2 replicated Study 1 in a sample of adults living in poverty (N = 36; Mage = 38.44, 88% female; family income = $25,625). The results of both studies showed EFT reduced DD, but process‐oriented EFT did not amplify the effect of EFT. Our findings suggest the key ingredient in EFT's effect on DD is self‐projection into the future. This was also the first study to show EFT improves DD in a sample living in poverty. [ABSTRACT FROM AUTHOR]

Background: Current theories in neuroscience emphasize the crucial role of individual differences in the brain contributing to the development of risk taking during adolescence. Yet, little is known about developmental pathways through which family risk factors are related to neural processing of risk during decision making, ultimately contributing to health risk behaviors. Using a longitudinal design, we tested whether neural risk processing, as affected by family multi‐risk index, predicted delay discounting and substance use. Method: One hundred and fifty‐seven adolescents (aged 13–14 years at Time 1, 52% male) were assessed annually three times. Family multi‐risk index was measured by socioeconomic adversity, household chaos, and family risk‐taking behaviors. Delay discounting was assessed by a computerized task, substance use by questionnaire data, and risk‐related neural processing by blood‐oxygen‐level‐dependent (BOLD) responses in the amygdala during a lottery choice task. Results: Family multi‐risk index at Time 1 was related to adolescent substance use at Time 3 (after controlling for baseline substance use) indirectly through heightened amygdala sensitivity to risks and greater delay discounting. Conclusions: Our results elucidate the crucial role of neural risk processing in the processes linking family multi‐risk index and the development of substance use. Furthermore, risk‐related amygdala activation and delay discounting are important targets in the prevention and treatment of substance use among adolescents growing up in high‐risk family environments. [ABSTRACT FROM AUTHOR]

Two common behavioral economic simulation tasks used to study cigarette smoking are the Cigarette Purchase Task, a measure of cigarette demand, and delay discounting, a measure of the subjective value of rewards as a function of delays to delivery. Few studies have evaluated whether combining these tasks enhances understanding of smoking beyond either alone. The current study represents an initial evaluation of the intersection between cigarette demand indices and delay discounting among pregnant smokers by examining associations between these measures and whether a woman makes antepartum quit attempts before entering prenatal care (a reliable predictor of eventual quitting). Participants were 159 pregnant women enrolled in a smoking‐cessation trial. Low Omax and shallow discounting were each associated with antepartum quit attempts. Participants were next categorized into four subgroups (low Omax, shallow discounting; low Omax, steep discounting; high Omax, shallow discounting; high Omax, steep discounting) using median splits. Those with shallow discounting and low Omax were more likely to have made quit attempts than each of the other three subgroups. That is, steep discounting appears to undermine the association of low Omax and efforts to quit smoking during pregnancy while high Omax overshadows any protective influence associated with shallow discounting. [ABSTRACT FROM AUTHOR]

Background: Delay discounting refers to the devaluation of a reward given increasing delays to delivery. Similarly, effort discounting refers to the devaluation of a reward given increasing effort required to obtain it. Individuals with substance use disorder show higher rates of delay discounting, exacerbating short‐term positive reinforcement at the expense of long‐term consequences. This study explores how effort discounting compares to delay discounting behavior among alcohol users as well as how these preferences change between monetary and alcohol rewards. Methods: A total of 100 participants completed an online survey through Amazon Mechanical Turk. Participant alcohol use was evaluated using DSM‐5 and the Alcohol Use Disorders Identification Test criteria. All participants completed 4 randomized discounting tasks involving delay or effort discounting, in which the reward was money or alcohol. A follow‐up experiment (n = 423) added the alcohol purchase task to assess alcohol valuation. Results: Individuals with greater alcohol use disorder (AUD) severity discounted future money and alcohol significantly more than those with less AUD. However, individuals meeting more DSM‐5 criteria were only willing to perform more effort for alcohol. The follow‐up experiment replicated these findings and demonstrated that individuals with greater AUD also showed an increased valuation of alcohol and alcohol value‐mediated effort discounting. Conclusions: These results suggest that individuals with greater AUD were less willing to wait for money or alcohol. While all participants were willing to work for money regardless of AUD severity, individuals with greater AUD showed increased valuation of alcohol drinks and were willing to exert more effort to obtain alcohol. Together, these results paint a picture of individuals with increased AUD as both more impulsive and willing to work to obtain alcohol, contributing to our understanding of decision making among individuals who abuse substances. [ABSTRACT FROM AUTHOR]

Statistical inference (including interval estimation and model selection) is increasingly used in the analysis of behavioral data. As with many other fields, statistical approaches for these analyses traditionally use classical (i.e., frequentist) methods. Interpreting classical intervals and p‐values correctly can be burdensome and counterintuitive. By contrast, Bayesian methods treat data, parameters, and hypotheses as random quantities and use rules of conditional probability to produce direct probabilistic statements about models and parameters given observed study data. In this work, we reanalyze two data sets using Bayesian procedures. We precede the analyses with an overview of the Bayesian paradigm. The first study reanalyzes data from a recent study of controls, heavy smokers, and individuals with alcohol and/or cocaine substance use disorder, and focuses on Bayesian hypothesis testing for covariates and interval estimation for discounting rates among various substance use disorder profiles. The second example analyzes hypothetical environmental delay‐discounting data. This example focuses on using historical data to establish prior distributions for parameters while allowing subjective expert opinion to govern the prior distribution on model preference. We review the subjective nature of specifying Bayesian prior distributions but also review established methods to standardize the generation of priors and remove subjective influence while still taking advantage of the interpretive advantages of Bayesian analyses. We present the Bayesian approach as an alternative paradigm for statistical inference and discuss its strengths and weaknesses. [ABSTRACT FROM AUTHOR]

The current article highlights key issues in defining, studying, and treating addiction, a concept related to but distinct from substance use disorders. The discussion is based upon a roundtable discussion at the 2017 annual meeting of the Research Society on Alcoholism where Warren K. Bickel and John C. Crabbe were charged with answering a range of questions posed by Kenneth J. Sher. All the presenters highlighted a number of central concerns for those interested in assessing and treating addiction as well as those seeking to conduct basic preclinical research that is amenable to meaningful translation to the human condition. In addition, the discussion illustrated both the power and limitations of using any single theory to explain multiple phenomena subsumed under the rubric of addiction. Among the major issues examined were the important differences between traditional diagnostic approaches and current concepts of addiction, the difficulty of modeling key aspects of human addiction in nonhuman animals, key aspects of addiction that have, to date, received little empirical attention, and the importance of thinking of recovery as a phenomenon that possibly involves processes distinct from those undergirding the development and maintenance of addiction. We discuss a range of central concerns for those interested in assessing and treating addiction as well as those seeking to conduct preclinical research that is amenable to meaningful translation to the human condition. Among the issues examined are the important differences between traditional diagnostic approaches and current concepts of addiction, the difficulty of modeling key aspects of human addiction in nonhuman animals, and key aspects of addiction that have received little empirical attention. [ABSTRACT FROM AUTHOR]

Background: The identification of new therapeutic targets to improve health behaviors among cancer survivors (CS) is likely to improve cancer treatment outcomes. Delay discounting (DD) rate is the degree to which one devalues rewards as a function of time to receipt. Lower DD rates (ie, prioritizing long-term over immediate rewards) are associated with healthier behaviors. CS often experience distress and thoughts of early mortality that can potentially shift priorities to the present and negatively impact DD rates, especially when newly diagnosed. Understanding relations between DD and health behaviors among CS will contribute to the examination of DD as a therapeutic target for improving health behaviors for CS.Method: CS (n = 1001) were recruited from a web panel and administered a web-based questionnaire. Multivariate models examined relations among DD rate, years since diagnosis, and 10 health behavior indicators. We hypothesized that 1) higher DD rates would be associated with fewer years since diagnosis, and 2) lower DD rates would be associated with healthier behaviors, moderated by years since diagnosis.Results: In general, higher DD rates were associated with fewer years since diagnosis. Higher DD rates were associated with more alcohol consumption, cigarette smoking, other tobacco use, tanning booth use, and conversely, greater adherence to annual primary care visits. A significant interaction between DD rate and years since diagnosis was not found.Conclusion: Lower DD rates are associated with several important healthy lifestyle behaviors. DD rate is a promising therapeutic target for new interventions to improve multiple health behaviors among CS. [ABSTRACT FROM AUTHOR]

Background: The delivery of monetary incentives contingent on verified abstinence is an effective treatment for alcohol use disorder. However, technological barriers to accurate, frequent biochemical verification of alcohol abstinence have limited the dissemination of this technique. Methods: In the present randomized parallel trial, we employed a breathalyzer that allows remote, user‐verified collection of a breath alcohol sample, text messaging, and reloadable debit cards for remote delivery of incentives to evaluate a contingency management treatment for alcohol use disorder that can be delivered with no in‐person contact. Treatment‐seeking participants with alcohol use disorder (n = 40) were recruited from the community and randomized to either a contingent or a noncontingent group (n = 20 each). The contingent group received nearly immediate monetary incentives each day they remotely provided negative breathalyzer samples. The noncontingent group received matched monetary payments each day they successfully provided samples independent of alcohol content. Groups were not masked as awareness of group contingencies was an essential intervention component. Results: The primary outcome of the intent‐to‐treat analyses (analyzed n = 40) was percent days abstinent as measured by the remote breathalyzer samples. Abstinence rates in the contingent group were 85%, which was significantly higher than the 38% recorded in the noncontingent group, corresponding to an odds ratio of 9.4 (95% CI = 4.0 to 22.2). Breathalyzer collection adherence rates were over 95%, and participant ratings of acceptability were also high. Conclusions: These results support the efficacy, acceptability, and feasibility of this remotely deliverable abstinence reinforcement incentive intervention for the initiation and near‐term maintenance of abstinence from alcohol in adults with alcohol use disorder. Due to low provider and participant burden, this procedure has the potential for broad dissemination. This parallel randomized trial examined a remotely delivered abstinence reinforcement intervention for alcohol use disorder and found strong support for the efficacy, feasibility, and acceptability of this approach. Participants randomized to the active Contingent treatment group were abstinent from alcohol 85% of days as verified by thrice daily remote breathalyzer readings, significantly more than the 38% in the Noncontingent control group. Due to low participant and practitioner burden, this model has potential for broad dissemination. [ABSTRACT FROM AUTHOR]

Abstract: Preventable chronic diseases are the leading cause of death in the majority of countries throughout the world, and this trend will continue for the foreseeable future. The potential to offset the social, economic, and personal burdens associated with such conditions depends on our ability to influence people's thought processes, decisions, and behaviors, all of which can be understood with reference to the brain itself. Within the health neuroscience framework, the brain can be viewed as a predictor, mediator, moderator, or outcome in relation to health‐related phenomena. This review explores examples of each of these, with specific reference to the primary prevention (i.e., prevention of initial onset) of chronic diseases. Within the topic of primary prevention, we touch on several cross‐cutting themes (persuasive communications, delay discounting of rewards, and self‐control), and place a special focus on obesity as a disorder influenced by both eating behavior and exercise habits. [ABSTRACT FROM AUTHOR]

Abstract: Model‐Based Systems Engineering (MBSE) is a mysterious concept that means many different things to different stakeholders. MBSE was envisioned to manage the increasing complexity within systems, by replacing traditional document‐based system engineering with a model‐based approach. However, more than a decade after MBSE was introduced, many systems engineering efforts still default to a “document‐like view” rather than integrated, “virtual,” representation of the system. This paper suggests a revised definition for MBSE which supports system design and analysis, throughout all phases of the system lifecycle, and through the collection of modeling languages, model‐based processes, structures, and presentation frameworks used to support the discipline of systems engineering in a model‐based or model‐driven context. To realize this definition, and an environment where the system is virtually represented, the long‐sought ontology must be attained for better definition and structure within MBSE. This paper explores how current MBSE methods can be extended to include an ontology. [ABSTRACT FROM AUTHOR]

This report describes an 11-year-old Percheron mare that presented with signs of colic and was ultimately diagnosed with bacterial peritonitis of unknown origin. Bacterial culture of a peritoneal fluid sample isolated 2 Clostridial species, one of which was strongly suspected to be Clostridium haemolyticum. The horse was markedly hypoalbuminaemic at presentation, leading to the development of low oncotic pressure and ventral oedema. The mare was administered a low molecular weight/low molar substitution hydroxyethyl starch solution in conjunction with other therapies that resulted in marked improvement of clinical signs. The purpose of this report is to describe the clinical findings associated with equine peritonitis associated with C. haemolyticum, a rarely identified pathogen in the horse. Secondly, this report serves to describe the beneficial effects of tetrastarch administration in a clinical case with severe hypoalbuminaemia and ventral oedema. [ABSTRACT FROM AUTHOR]

A 10-h-old Thoroughbred foal presented with clinical signs consistent with neonatal encephalopathy including absent suckling behaviour, lack of affinity for the mare and seizures. The foal was provided supportive care and treated with broad-spectrum antimicrobials and fed via naso-oesophageal tube. In addition, magnetic resonance imaging (MRI) was performed to investigate for structural changes that might be evident with equine neonatal encephalopathy. Notable findings on MRI included hyperintensity of the basal nuclei and superficial layers of the ventral cerebral hemispheres as well as the ventral thalamic nuclei and rostral aspect of the ventral midbrain. These imaging changes were consistent with the counterpart disease in infants and are the first to document MRI changes in a foal with neonatal encephalopathy. This report serves as an initial description of MRI findings associated with the presumed diagnosis of equine neonatal encephalopathy and also serves to solicit future diagnostic imaging studies that may help elucidate the pathophysiology and prognosis of equine neonatal encephalopathy. [ABSTRACT FROM AUTHOR]

The developmental period of adolescence is characterized by increasing incidence of health risk behaviors ( HRBs). Based on theoretical models that emphasize the moderating role of cognitive control, this study examined how neural correlates of cognitive control and risk sensitivity interact to predict HRBs among late adolescents (17-20 years). Neuroimaging data indicate that risk-related hemodynamic activity in the anterior insula during anticipation of uncertain outcomes predicts HRBs among late adolescents exhibiting greater dorsal anterior cingulate cortex (d ACC) activity during a cognitive interference task but not among late adolescents requiring less d ACC activity. These results present neural evidence for a significant moderating effect of cognitive control on the link between risk sensitivity and HRBs among late adolescents. [ABSTRACT FROM AUTHOR]

Basic research on delay discounting, examining preference for smaller-sooner or larger-later reinforcers, has demonstrated a variety of findings of considerable generality. One of these, the magnitude effect, is the observation that individuals tend to exhibit greater preference for the immediate with smaller magnitude reinforcers. Delay discounting has also proved to be a useful marker of addiction, as demonstrated by the highly replicated finding of greater discounting rates in substance users compared to controls. However, some research on delay discounting rates in substance users, particularly research examining discounting of small-magnitude reinforcers, has not found significant differences compared to controls. Here, we hypothesize that the magnitude effect could produce ceiling effects at small magnitudes, thus obscuring differences in delay discounting between groups. We examined differences in discounting between high-risk substance users and controls over a broad range of magnitudes of monetary amounts ($0.10, $1.00, $10.00, $100.00, and $1000.00) in 116 Amazon Mechanical Turk workers. We found no significant differences in discounting rates between users and controls at the smallest reinforcer magnitudes ($0.10 and $1.00) and further found that differences became more pronounced as magnitudes increased. These results provide an understanding of a second form of the magnitude effect: That is, differences in discounting between populations can become more evident as a function of reinforcer magnitude. [ABSTRACT FROM AUTHOR]

Background: Episodic future thinking (EFT) requires an individual to vividly pre-experience a realistic future event. Inspired by previous reports of reducing delay discounting following EFT in other populations, we examined the effects of engaging alcohol-dependent individuals in EFT or episodic recent thinking (ERT; control) to examine its effects on delay discounting and alcohol purchasing. Methods: Participants (n = 50) with alcohol dependence were allocated into EFT or ERT groups and asked to generate positive future or recent past events for each of 5 time points. Participants then completed a delay-discounting task, during which event cues were displayed, and a hypothetical alcohol purchase task. Results: EFT significantly increased valuation of future monetary rewards, while decreasing initial consumption (Q0) of alcoholic drinks indicative of lower demand intensity. Two additional findings suggest potential moderators of this effect. EFT more readily influenced individuals with lower Alcohol Use Disorders Identification Test scores, and self-reported cue valence differed between groups. Conclusions: Together, these results suggest a widening of alcohol-dependent individuals' temporal window following engagement of EFT. While our data suggest that EFT may be moderated by certain susceptibility criteria, exercises such as EFT could be easily adaptable as a potential therapeutic tool for use in rehabilitation programs. [ABSTRACT FROM AUTHOR]

Although humans do not always respond rationally, decades of behavioral economic research have brought order to these irrational patterns of responding, particularly in individuals whose maladaptive behavior and the neurobiological dysregulation that presumably undergirds it directly impact their health (drug addiction and obesity). These findings have given rise to a new paradigm, reinforcer pathologies. Specifically, poor health decisions are consistently related to an inability to value the future and an overvaluation of specific unhealthy rewards (drugs, cake, etc.). The current review briefly describes these robust areas of research with the goal of adapting the present findings to improve staff performance. [ABSTRACT FROM AUTHOR]

Perforation of the oesophagus is an uncommon event that can occur for a variety of reasons. While cervical ruptures of the oesophagus can be managed successfully, intrathoracic lesions warrant a far worse prognosis. Intrathoracic rupture of the oesophagus can occur spontaneously, with no known history of oesophageal obstruction, and may not be identified until a septic pleuropneumonia develops. This report describes the history, clinical presentation, response to therapy and outcome of 5 cases of intrathoracic oesophageal perforation and secondary septic pleuropneumonia. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the pharmacokinetic properties and physiologic effects of a single oral dose of alprazolam in horses. Seven adult female horses received an oral administration of alprazolam at a dosage of 0.04 mg/kg body weight. Blood samples were collected at various time points and assayed for alprazolam and its metabolite, α-hydroxyalprazolam, using liquid chromatography/mass spectrometry. Pharmacokinetic disposition of alprazolam was analyzed by a one-compartmental approach. Mean plasma pharmacokinetic parameters (±SD) following single-dose administration of alprazolam were as follows: Cmax 14.76 ± 3.72 ng/mL and area under the curve (AUC0-∞) 358.77 ± 76.26 ng·h/mL. Median (range) Tmax was 3 h (1-12 h). Alpha-hydroxyalprazolam concentrations were detected in each horse, although concentrations were low (Cmax 1.36 ± 0.28 ng/mL). Repeat physical examinations and assessment of the degree of sedation and ataxia were performed every 12 h to evaluate for adverse effects. Oral alprazolam tablets were absorbed in adult horses and no clinically relevant adverse events were observed. Further evaluation of repeated dosing and safety of administration of alprazolam to horses is warranted. [ABSTRACT FROM AUTHOR]

Prior research indicates that religiousness is related negatively to adolescent health risk behaviors, yet how such protective effects operate is not well understood. This study examined the longitudinal associations among organizational and personal religiousness, delay discounting, and substance use initiation (alcohol, cigarette, and marijuana use). The sample was comprised of 106 early adolescents (10-13 years of age, 52% female) who were not using substances at Time 1. Path analyses suggested that high levels of personal religiousness at Time 1 were related to low levels of substance use at Time 2 (2.4 years later), mediated by low levels of delay discounting. Delay discounting appears to be an important contributor to the protective effect of religiousness on the development of substance use among adolescents. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses reports within the issue on topics including delay discounting, nicotine deprivation,and impulsive choice.

The study of delay discounting, or valuation of future rewards as a function of delay, has contributed to understanding the behavioral economics of addiction. Accurate characterization of discounting can be furthered by statistical model selection given that many functions have been proposed to measure future valuation of rewards. The present study provides a convenient Bayesian model selection algorithm that selects the most probable discounting model among a set of candidate models chosen by the researcher. The approach assigns the most probable model for each individual subject. Importantly, effective delay 50 (ED50) functions as a suitable unifying measure that is computable for and comparable between a number of popular functions, including both one- and two-parameter models. The combined model selection/ED50 approach is illustrated using empirical discounting data collected from a sample of 111 undergraduate students with models proposed by Laibson (1997); Mazur (1987); Myerson & Green (1995); Rachlin (2006); and Samuelson (1937). Computer simulation suggests that the proposed Bayesian model selection approach outperforms the single model approach when data truly arise from multiple models. When a single model underlies all participant data, the simulation suggests that the proposed approach fares no worse than the single model approach. [ABSTRACT FROM AUTHOR]