Combined expectancies of alcohol and e-cigarette use relate to higher alcohol use

Electronic cigarettes (e-cigs) were created to approximate the look, feel, and experience of using a cigarette. Since cigarette and alcohol use co-occur, we hypothesized that e-cig and alcohol use also co-occur, likely due to shared positive drug expectations. Using self-report data from two independent samples of community-dwelling alcohol using adults, the present study: (1) modified the Nicotine and Other Substance Interaction Expectancy Questionnaire (NOSIE) to assess expectancies of combined e-cig and alcohol use (i.e. the individuals perceived likelihood of using e-cigs and alcohol together; NOSIE-ER); and (2) examined the relationships among e-cig use, expectancies, and alcohol use across e-cig use status. In the first sample (N=692, mean age=32.6, SD=9.74, 50.7% female, 82.2% Caucasian), exploratory factor analysis suggested the presence of two factors: (1) alcohol use leads to e-cig use (Scale 1; α=0.85); and (2) e-cig use leads to alcohol use (Scale 2; α=0.91). In the second sample (N=714, mean age=34.1, SD=10.89, 47.8% female, 75.6% Caucasian), confirmatory factor analysis supported this factor structure (χ(2)=47.00, p<0.01, df=19; RMSEA=0.08, 90% CI=0.05-0.11; TLI=0.99; CFI=0.99). Compared to non e-cig users, e-cig users had significantly higher problematic alcohol use in both samples (b's=0.09 to 0.14, p's<.05). Expectancies of combined e-cig and alcohol use were significantly related to problematic alcohol use (b's=-0.92 to 0.26, p's<.05). In sum, e-cig use is related to alcohol use and expectancies of combined e-cig and alcohol use; consequently, reshaping of beliefs about needs or desires to co-use could be a prime point of intervention

UPPS-P Model Impulsivity and Marijuana Use Behaviors in Adolescents: A Meta-Analysis

Background Impulsivity is often included as a risk factor in models of adolescent marijuana use behaviors; however, the magnitude of the association between impulsivity and marijuana use behaviors is variable across studies. The present study reviewed existent literature to 1) quantify the relationship between separable impulsivity-related traits and both marijuana use and negative marijuana consequences and 2) quantify the size of the effect of gender on these relationships. Method Thirty-eight studies (41 independent samples) were meta-analyzed using a random effects model to examine the relationship between impulsivity traits and marijuana use behaviors. Results Marijuana use was significantly related to all impulsivity-related traits except lack of perseverance (r’s ranging from 0.13–0.23, p’s < 0.01). Negative marijuana consequences were only significantly related to sensation seeking, lack of planning, and positive urgency (r’s ranging from 0.37–0.39, p’s < 0.01). Effects were small for marijuana use, but medium for negative marijuana consequences. Gender was not a significant moderator of any relationships. Conclusions Impulsivity-related traits had more robust relationships with negative marijuana consequences than marijuana use, suggesting impulsivity-related traits are important in differentiating adolescents most likely to experience negative consequences from marijuana use. Few relationships examined gender and many of the impulsivity-related traits, other than sensation seeking. Data and trends suggest a more multi-dimensional approach to marijuana use and consequences is warranted

Sparse Fault-Tolerant BFS Trees

This paper addresses the problem of designing a sparse {\em fault-tolerant} BFS tree, or {\em FT-BFS tree} for short, namely, a sparse subgraph $T$ of the given network $G$ such that subsequent to the failure of a single edge or vertex, the surviving part $T'$ of $T$ still contains a BFS spanning tree for (the surviving part of) $G$. Our main results are as follows. We present an algorithm that for every $n$-vertex graph $G$ and source node $s$ constructs a (single edge failure) FT-BFS tree rooted at $s$ with O(n \cdot \min\{\Depth(s), \sqrt{n}\}) edges, where \Depth(s) is the depth of the BFS tree rooted at $s$. This result is complemented by a matching lower bound, showing that there exist $n$-vertex graphs with a source node $s$ for which any edge (or vertex) FT-BFS tree rooted at $s$ has $\Omega(n^{3/2})$ edges. We then consider {\em fault-tolerant multi-source BFS trees}, or {\em FT-MBFS trees} for short, aiming to provide (following a failure) a BFS tree rooted at each source $s\in S$ for some subset of sources $S\subseteq V$. Again, tight bounds are provided, showing that there exists a poly-time algorithm that for every $n$-vertex graph and source set $S \subseteq V$ of size $\sigma$ constructs a (single failure) FT-MBFS tree $T^*(S)$ from each source $s_i \in S$, with $O(\sqrt{\sigma} \cdot n^{3/2})$ edges, and on the other hand there exist $n$-vertex graphs with source sets $S \subseteq V$ of cardinality $\sigma$, on which any FT-MBFS tree from $S$ has $\Omega(\sqrt{\sigma}\cdot n^{3/2})$ edges. Finally, we propose an $O(\log n)$ approximation algorithm for constructing FT-BFS and FT-MBFS structures. The latter is complemented by a hardness result stating that there exists no $\Omega(\log n)$ approximation algorithm for these problems under standard complexity assumptions

Kinetic collision detection between two simple polygons

AbstractWe design a kinetic data structure for detecting collisions between two simple polygons in motion. In order to do so, we create a planar subdivision of the free space between the two polygons, called the external relative geodesic triangulation, which certifies their disjointness. We show how this subdivision can be maintained as a kinetic data structure when the polygons are moving, and analyze its performance in the kinetic setting

Beliefs About the Direct Comparison of E-Cigarettes and Cigarettes

Background: Recent data suggests that positive beliefs about electronic cigarettes (e-cigs) use can lead to later e-cig use. Considering that many advertisements claim that e-cigs are superior to cigarettes, individuals' likelihood to view e-cigs more favorably than cigarettes can also influence subsequent e-cig use; however, no studies have directly assessed such a comparison. Objectives: The present study created and validated the Comparing E-Cigarettes and Cigarettes questionnaire (CEAC), which asks individuals to directly compare e-cigs and cigarettes on a number of dimensions, in two independent samples. Methods: In sample 1 (451 undergraduates; mean age = 20.35, SD = 5.44, 72.4% female, 73.4% Caucasian) we explored the factor structure of the CEAC and in sample 2 (699 community adults collected via Amazon's Mechanical Turk; mean age = 34.04, SD = 10.9, 47.7% female, 83.3% Caucasian) we replicated the factor structure. Results: Exploratory factor analysis suggested a three-factor structure: General Benefits (α = 0.80), General Effects (α = 0.86), and Health Benefits (α = 0.88), which was replicated via confirmatory factor analysis, χ2 = 4.36; RMSEA = 0.07, 90% CI = 0.06–0.08; TLI = 0.99; CFI = 0.99, and was relatively invariant across product use and gender. Individuals reported viewing e-cigs as safer and more beneficial than cigarettes and these beliefs were higher in e-cig users. Conclusions: Future work should establish how these comparative beliefs are influenced by e-cig use and/or influence subsequent transition to and increases in e-cig use. Although e-cigs are likely less harmful than cigarettes, and thus these comparative beliefs represent that state of nature, e-cigs are not completely without risk

Transitioning from cigarettes to electronic cigarettes increases alcohol consumption

Objective Electronic cigarettes (e-cigs) are a nicotine delivery device that have recently been linked to alcohol use. Many individuals that smoke cigarettes transition to e-cigs as an alternative to cigarette use, despite potential negative health effects of e-cigs. No research to date has examined how former smokers that have transitioned to e-cigs differ from former smokers that do not use e-cigs, particularly in relation to alcohol use. Further, no research has examined how former smokers that use e-cigs regularly or socially may differ in alcohol consumption. Method Using an online community dwelling sample (Former smokers N=198, mean age=34.70, SD=11.45, 56.1% female, 78.3% Caucasian, 37.9% e-cig users), the present study assessed smoking status and alcohol use, with the latter assessed using a Timeline Followback calendar and the Alcohol Use Disorder Identification Test (AUDIT). Results In all former smokers, total drinks (b=4.01, p=0.02) and average drinks per drinking day (b=0.61, p=.01) were both related to e-cig use status, with e-cig users reporting higher alcohol consumption. Among e-cig using former smokers, social users, but not regular users, showed positive relationships with AUDIT scores, b=1.90, p=.02, total drinks, b=9.12, p<.001, average drinks, b=0.98, p=.006, and hazardous drinking status, OR=3.21, p=.01. Conclusions Findings suggest that: (1) former smokers who use e-cigs may have a potential for higher alcohol use; and (2) those who use e-cigs socially may be at heightened risk for hazardous patterns of alcohol consumption. This should be taken into consideration by healthcare providers

Energetic Cost of Ichthyophonus Infection in Juvenile Pacific Herring (Clupea pallasii)

The energetic costs of fasting and Ichthyophonus infection were measured in juvenile Pacific herring (Clupea pallasii) in a lab setting at three temperatures. Infected herring incurred significant energetic costs, the magnitude of which depended on fish condition at the time of infection (fat versus lean). Herring that were fed continually and were in relatively good condition at the time of infection (fat) never stored lipid despite ad libitum feeding. In feeding herring, the energetic cost of infection was a 30% reduction in total energy content relative to controls 52 days post infection. Following food deprivation (lean condition), infection caused an initial delay in the compensatory response of herring. Thirty-one days after re-feeding, the energetic cost of infection in previously-fasted fish was a 32% reduction in total energy content relative to controls. Body composition of infected herring subsequently recovered to some degree, though infected herring never attained the same energy content as their continuously fed counterparts. Fifty-two days after re-feeding, the energetic cost of infection in previously-fasted fish was a 6% reduction in total energy content relative to controls. The greatest impacts of infection occurred in colder temperatures, suggesting Ichthyophonus-induced reductions in body condition may have greater consequences in the northern extent of herring's range, where juveniles use most of their energy reserves to survive their first winter

To know or not to know? Dilemmas for women receiving unknown oocyte donation

BACKGROUND: This study aims to provide insight into the reasons for choosing an unknown oocyte donor and to explore recipients’ feelings and wishes regarding donor information. METHODS: In-depth interviews were carried out with 11 women at different stages of treatment. Seven were on a waiting list and four have given birth to donor oocyte babies. The interviews were analysed using interpretative phenomenological analysis. RESULTS: The choice of unknown donor route was motivated by a wish to feel secure in the role of mother as well as to avoid possible intrusions into family relationships. The information that is available about unknown donors is often very limited. In the preconception phase of treatment, some participants wanted more information about the donor but others adopted a not-knowing stance that protected them from the emotional impact of needing a donor. In the absence of information that might normalize her, there was a tendency to imagine the donor in polarised simplistic terms, so she may be idealized or feared. Curiosity about the donor intensified once a real baby existed, and the task of telling a child was more daunting when very little was known about the donor. A strong wish for same-donor siblings was expressed by all of the participants who had given birth. CONCLUSIONS: This qualitative study throws light on the factors that influence the choice of unknown donation. It also highlights the scope for attitudes to donor information to undergo change over the course of treatment and after giving birth. The findings have implications for pretreatment counselling and raise a number of issues that merit further exploration