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Background: Given the growing legalization of recreational marijuana use and related increase in its prevalence in the United States, it is important to understand marijuana's appeal. We used a behavioral economic (BE) approach to examine whether the reinforcing properties of marijuana, including "demand" for marijuana, varied as a function of its perceived quality.Methods: Using an innovative, Web-based marijuana purchase task (MPT), a sample of 683 young-adult recreational marijuana users made hypothetical purchases of marijuana across three qualities (low, mid and high grade) at nine escalating prices per joint, ranging from $0/free to $20.Results: We used nonlinear mixed effects modeling to conduct demand curve analyses, which produced separate demand indices (e.g., Pmax, elasticity) for each grade of marijuana. Consistent with previous research, as the price of marijuana increased, marijuana users reduced their purchasing. Demand also was sensitive to quality, with users willing to pay more for higher quality/grade marijuana. In regression analyses, demand indices accounted for significant variance in typical marijuana use.Conclusions: This study illustrates the value of applying BE theory to young adult marijuana use. It extends past research by examining how perceived quality affects demand for marijuana and provides support for the validity of a Web-based MPT to examine the appeal of marijuana. Our results have implications for policies to regulate marijuana use, including taxation based on the quality of different marijuana products. [ABSTRACT FROM AUTHOR]

Background: Most patients with single ventricle congenital heart disease (SV) are now expected to survive to adulthood. Medical comorbidities are common in SV. Methods: We used data from 43 pediatric hospitals in the 2004 to 2011 Pediatric Health Information System database to identify patients ≥18years of age admitted with International Classification of Diseases-9th Revision codes for a diagnosis of either hypoplastic left heart syndrome (HLHS), tricuspid atresia (TA) or common ventricle (CV). Primary (PD) and secondary diagnoses (SD), length of stay (LOS) and hospital charges were determined. Multilevel models were used to evaluate differences in demographics, diagnoses, and admission outcomes among the three subgroups (HLHS, TA, and CV). Interactions of charges with PD and admission year were examined using ANOVA. Results: There were 801 SV patients with 1330 admissions during the study period. Mean age was 24.8±6.2years (55% male) and mean LOS was 6.8±11.3days. Total hospital charges were $135million with mean charge per admission of $101,131±205,808. The mean charge per day was $15,407±16,437. Hospital charges correlated with PD group (p<0.001). Admission rate remained stable (~180/year) from 2006 to 2011. LOS decreased (p=0.0308) and hospital charges per day increased across the study period (p<0.001). PD was non-cardiac in 28% of admissions. Liver-related conditions were more common in patients with HLHS (p<0.001). Conclusions: Hospitalization costs in adults with SV are significant and are impacted by comorbid medical conditions. Hospitalization rates for adults with SV are not increasing. Gastroenterologic comorbidities including protein-losing enteropathy (PLE) are common in HLHS. [ABSTRACT FROM AUTHOR]

Williams syndrome (WS) is a congenital, developmental disorder affecting 1 in 8,000 live births. The corrected QT (QTc) interval is prolonged in 13% of patients with WS. No data exist characterizing the ambulatory electrocardiographic findings in WS. A retrospective review of all patients with WS evaluated at our institution from January 1, 1980 to December 31, 2007 was performed. Patients with ≥1 ambulatory electrocardiogram (AECG) with sinus rhythm and measurable intervals were included. QTc measurements were made at the minimum and maximum heart rate. Logistic regression analysis was used to evaluate the correlation of ventricular ectopic complexes with QTc measurements. A statistical probability of p <0.05 was considered significant. Of 270 patients identified, 32 had AECGs available for review. Complete data were available for 56 AECGs from 26 patients (15 female; 58%). Their mean age was 15.6 ± 7.2 years at the initial AECG and 20.6 ± 8.6 years for all AECGs. The QTc interval increased with increasing heart rate. Ventricular premature complexes occurred in 40 (73%) of 56 AECGs and 21 (81%) of 26 patients. Ventricular tachycardia occurred in 5 (9%) of 56 AECGs and 4 (15%) of 26 patients. The mean length of ventricular tachycardia was 3.6 ± 0.5 beats at a rate of 171 ± 40 beats/min. The QTc interval at the minimum heart rate correlated directly with age (p <0.001), total ventricular premature complexes (p = 0.007), ventricular couplets (p = 0.002), and ventricular tachycardia (p = 0.011). The QTc interval at the maximum heart rate correlated directly with age (p <0.001), total ventricular premature complexes (p = 0.016), and ventricular couplets (p = 0.006). In conclusion, the QTc interval correlated with ventricular ectopic complexes in patients with WS. The type of ventricular ectopic complexes suggested an alternate etiology of the QTc prolongation seen in WS from that seen in congenital long QT syndrome. [Copyright &y& Elsevier]

Abstract: We examined the social networks and alcohol use of a community-based sample of nonstudent emerging adults (N =59). The research examined (1) personal network characteristics and the drinking habits of its members, (2) the link between network alcohol use and personal alcohol involvement, (3) perceived social norms as they related to network alcohol use, and (4) relationship between perceived social norms and personal alcohol involvement. Men and women (M age=27years) were equally represented in the social network. Level of educational attainment of members was diverse. On average, respondents were in contact on a daily basis with network members and about 38% of the network was known between 1 and 5years. The majority (57%) of the network consisted of household or family members. There were some associations between network drinking and personal alcohol involvement. The proportion of “drinking buddies” in one''s network was directly associated with perceived drinking norms. Perceived drinking norms also were positively associated with personal alcohol use, alcohol-related problems, and approval of drinking behaviors. Findings from this study have implications for understanding social factors in the drinking behavior of nonstudent emerging adults and could inform the development of effective prevention and treatment interventions for this important, but understudied group of drinkers. [Copyright &y& Elsevier]

Williams syndrome (WS) affects 1 in 8,000 live births and has a high risk of sudden death. No previous studies have evaluated corrected QT (QTc) prolongation in WS. Retrospective review of all patients with WS evaluated at our institution from January 1, 1980 to December 31, 2007 was performed. WS was diagnosed by a medical geneticist and/or by fluorescence in situ hybridization. Patients with ≥1 electrocardiogram (ECG) with sinus rhythm and measurable intervals were included. Normal control ECGs were identified from a large clinical database. Corrected JT (JTc) interval was calculated when QRS and QTc intervals were prolonged. QTc interval ≥460 ms and JTc interval >340 ms were defined as prolonged. Prevalence comparisons were made using Fisher''s exact test. Statistical probability of <0.05 was considered significant. Of 270 patients identified, 188 had ECGs for review. Complete data were present in 499 of 517 ECGs (patients'' mean age 10.3 ± 9.9 years); 1,522 normal ECGs of age-similar patients composed the control group. QTc prolongation prevalences were 2.0% in controls and 13.6% in WS (p <0.0001); in those, JTc prolongation prevalences were 1.8% in controls and 11.7% in WS (p <0.0001). Four patients died during follow-up; 2 had QTc prolongation and 1 died during noncardiac surgery. Another patient with QTc prolongation sustained cardiac arrest during a procedure. In conclusion, cardiac repolarization is prolonged in WS. Presence of prolonged cardiac repolarization may contribute to the high incidence of periprocedural mortality in these patients. All patients with WS should be screened for cardiac repolarization abnormalities, especially before surgery. [Copyright &y& Elsevier]

Williams syndrome (WS) is a congenital disorder affecting the vascular, connective tissue, and central nervous systems of 1 in 8,000 live births. Previous reports have reported high frequencies of cardiovascular abnormalities (CVAs) in small numbers of patients with WS. A retrospective review was undertaken of patients with WS evaluated at our institution from January 1, 1980 through December 31, 2007. WS was diagnosed by an experienced medical geneticist and/or by fluorescence in situ hybridization. CVAs were diagnosed using echocardiography, cardiac catheterization, or computed tomographic angiography. Freedom from intervention was determined using Kaplan-Meier analysis. The study group was 270 patients with WS. The age at presentation was 3.3 ± 5.9 years with follow-up of 8.9 ± 9.0 years (range 0 to 56.9). CVAs were present in 82% of the patients. The most common lesions were supravalvar aortic stenosis in 45% and peripheral pulmonary stenosis in 37%; 20% had both. Other common lesions included mitral valve prolapse and regurgitation in 15%, ventricular septal defect in 13%, and supravalvar pulmonary stenosis in 12%. Surgical or catheter-based interventions were performed in 21%. The rate of freedom from intervention was 91%, 81%, 78%, 72%, and 62% at 1, 5, 10, 20, and 40 years. Eight patients died. In conclusion, CVAs are common in patients with WS, but supravalvar aortic stenosis and peripheral pulmonary stenosis occurred less frequently in this large cohort than previously reported. In patients with WS and CVAs, interventions are common and usually occur by 5 years of age. Most patients with WS do not require intervention during long-term follow-up, and the overall mortality has been low. [Copyright &y& Elsevier]

Abstract: In college students, solitary heavy drinking (i.e., while alone) is associated with depression and with higher rates of drinking problems than heavy drinking in social contexts. This study explored the relationship among heavy episodic drinking context, suicidal ideation, and drinking motives among underage college drinkers (n =91) with a history of passive suicidal ideation. Participants completed measures of depression, suicidal ideation, alcohol consumption and problems, and drinking motives. Multiple regression analyses revealed that suicidal ideation, but not depression, was significantly related to solitary heavy drinking. Neither was related to social heavy drinking. Enhancement motives for drinking, but not other drinking motives (i.e., social, conformity, drinking to cope), were significantly associated with social heavy drinking. In contrast, only drinking to cope was associated with solitary heavy drinking. These findings suggest that greater suicidal ideation is associated with greater frequency of becoming intoxicated while alone, and that this drinking is motivated by attempts to cope. Solitary heavy drinking is a potentially dangerous coping strategy for an individual experiencing suicidal ideation. [Copyright &y& Elsevier]

Abstract: Abundances of particles, total bacteria, and particulate extracellular polymeric substances (pEPS) in Arctic sea ice were tracked through a winter season to examine the impact of combined extremes of low temperature and high salinity on the prokaryotic microbial community. Three horizons, centered at depths of 25, 45, and 65 cm from the ice surface, with mean seasonal temperatures of −20, −17, and −13 °C, respectively, were sampled 16 times over the course of 12 weeks. Microscopic counts of bacteria (stained with DAPI) and particles (stained with acridine orange) reflected the dynamic conditions of the growing ice sheet, with greater abundances and variability in the upper ice horizons compared to the lower. The trend of higher particle and bacterial abundances in the upper ice was corroborated by several full-depth profiles taken during the expedition, which also displayed significantly decreasing cell abundance with depth. Bacterial abundance declined slowly and significantly with time in the upper and middle ice horizons, but not in the lowest, suggesting that much of the prokaryotic microbial community is resilient to extreme environmental conditions. We found that pEPS concentrations increased significantly with time and with decreasing temperatures in all depth horizons, which may lend support to the argument that sea ice bacteria produce EPS in situ as a cryoprotectant. [Copyright &y& Elsevier]

Abstract: Underage drinkers typically have not developed regular patterns of drinking and so are likely to exhibit situational variation in alcohol intake, including binge drinking. Information about such variation is not well captured by quantity/frequency (QF) measures, which require that drinkers blend information over time to derive a representative estimate of “typical” drinking. The Timeline Followback (TLFB) method is designed to retrospectively capture situational variations in drinking during a specific period of time. We compared our newly-developed Self-administered TLFB (STLFB) measure to a QF measure for reporting alcohol intake. Our sample of 429 (men=204; women=225) underage (i.e., age 18–20 years) drinkers completed the two drinking measures and reported on alcohol problems. The STLFB and QF measures converged in assessing typical daily intake, but the STLFB provided more information about situational variations in alcohol use and better identification of regular versus intermittent binge drinkers. Regular binge drinkers reported more alcohol problems. The STLFB is an easy-to-administer measure of variations in alcohol intake, which can be useful for understanding drinking behavior. [Copyright &y& Elsevier]

Abstract: Young adult men and women (N =53) who regularly consume malt liquor (i.e., 40 oz/week) participated in 10 semi-structured focus groups. Group transcripts were analyzed using a multilevel process that focused on recurring themes across multiple groups. Commonly identified themes encompassed positive and negative qualities of malt liquor as well as contexts in which malt liquor was consumed. Some of the themes were corroborated by quantitative data on drinking behavior and other variables. The focus groups were designed to explore the unique characteristics of malt liquor (low price, high alcohol content, large volume packaging) that enhance consumption patterns and increase risk for excessive alcohol use. The combination of qualitative and quantitative data provides a unique and useful perspective for identifying issues for future research on malt liquor consumption. [Copyright &y& Elsevier]

Abstract: An active control strategy for vibration control of structures using ATMDs is proposed. The control strategy incorporates the minimax criteria for shaping the frequency response function (FRF) of the structure–TMD system and the bang–bang control law with a control force applied to a TMD. In the control scheme, the control law using bang–bang control is obtained by minimising the time derivative of a Lyapunov function of the open-loop structural system [Wu Z, Soong TT. Modified bang–bang control law for structural control implementation. Journal of Engineering Mechanics 1996;122(8):771–7] and is used to control the ATMD. In addition, the corresponding FRF for the coupled structure–ATMD system is reshaped by changing the tuning parameter of the TMD (when there is no control force applied), such that peaks in the FRF of the structure are equal in magnitude. When the active control is ineffective or is turned off, the damper system acts as a passive TMD. The proposed strategy is compared to another conventional control strategy, the Linear Quadratic Controller (LQC) applied to the structure–TMD system and the advantages are highlighted. The system is examined under harmonic and random excitations. [Copyright &y& Elsevier]

The Arabidopsis genome sequencing in 2000 gave to science the first blueprint of a vascular plant. Its successful completion also prompted the US National Science Foundation to launch the Arabidopsis 2010 initiative, the goal of which is to identify the function of each gene by 2010. In this study, an exhaustive analysis of The Institute for Genomic Research (TIGR) and The Arabidopsis Information Resource (TAIR) databases, together with all currently compiled EST sequence data, was carried out in order to determine to what extent the various metabolic networks from phenylalanine ammonia lyase (PAL) to the monolignols were organized and/or could be predicted. In these databases, there are some 65 genes which have been annotated as encoding putative enzymatic steps in monolignol biosynthesis, although many of them have only very low homology to monolignol pathway genes of known function in other plant systems. Our detailed analysis revealed that presently only 13 genes (two PALs, a cinnamate-4-hydroxylase, a p-coumarate-3-hydroxylase, a ferulate-5-hydroxylase, three 4-coumarate-CoA ligases, a cinnamic acid O-methyl transferase, two cinnamoyl-CoA reductases) and two cinnamyl alcohol dehydrogenases can be classified as having a bona fide (definitive) function; the remaining 52 genes currently have undetermined physiological roles. The EST database entries for this particular set of genes also provided little new insight into how the monolignol pathway was organized in the different tissues and organs, this being perhaps a consequence of both limitations in how tissue samples were collected and in the incomplete nature of the EST collections. This analysis thus underscores the fact that even with genomic sequencing, presumed to provide the entire suite of putative genes in the monolignol-forming pathway, a very large effort needs to be conducted to establish actual catalytic roles (including enzyme versatility), as well as the physiological function(s) for each member of the (multi)gene families present and the metabolic networks that are operative. Additionally, one key to identifying physiological functions for many of these (and other) unknown genes, and their corresponding metabolic networks, awaits the development of technologies to comprehensively study molecular processes at the single cell level in particular tissues and organs, in order to establish the actual metabolic context. [Copyright &y& Elsevier]

Cardiovascular disease (CVD)-related mortality has declined substantially in the United Kingdom (UK) in recent decades, but the continued relevance of conventional risk factors for prediction of CVD mortality throughout the life-course is uncertain. We compared the 10-year risks and lifetime risks of CVD mortality associated with conventional risk factors recorded in middle and old age. The Whitehall study was a prospective study of 19,019 male London civil servants (mean age 52 years) when enrolled in 1967–1970 and followed-up for 50 years for cause-specific mortality. In 1997, 7044 (83%) survivors (mean age 77 years) were re-surveyed. The 10-year and lifetime risks of CVD mortality were estimated by levels of CVD risk factors recorded in middle-age and old-age, respectively. By July 2020, 97% had died (22%, 51% and 80% before age 70, 80 and 90 years, respectively) and 7944 of 17,673 deaths (45%) were from CVD. The 10-year and lifetime risks of CVD death increased linearly with higher levels of CVD risk factors recorded in middle-age and in old-age. Individuals in the top versus bottom 5% of CVD risk scores in middle age had a 10.3% (95% CI:7.2–13.4) vs 0.6% (0.1–1.2) 10-year risk of CVD mortality, a 61.4% (59.4–65.3) vs 31.3% (24.1–34.5) lifetime risk of CVD mortality and a 12-year difference in life expectancy from age 50 years. The corresponding differences using a CVD risk score in old-age were 11.0% (4.4–17.5) vs 0.8% (0.0–2.2) for 10-year risk and 42.1% (28.2–50.0) vs 30.3% (6.0–38.0) for lifetime risk of CVD mortality and a 6-year difference in life expectancy from age 70 years. Conventional risk factors remained highly predictive of CVD mortality and life expectancy through the life-course. The findings highlight the relevance of estimation of both lifetime risks of CVD and 10-year risks of CVD for primary prevention of CVD. [ABSTRACT FROM AUTHOR]

An outbreak of tuberculosis (TB), caused by Mycobacterium bovis, was investigated in a small herd of llamas (Lama glama). Based on three ante-mortem diagnostic methods (clinical signs, tuberculin skin test reactions, and 'Rapid Test' serology), 12 llamas were selected for examination post-mortem. Grossly visible lesions suspicious of TB were observed in eight animals, four of which had exhibited clinical signs, one was a skin test 'reactor', and three had been seropositive. M. bovis was isolated from seven of these eight animals. Clinical signs combined with serology were found to be useful in identifying infected animals, but tuberculin skin testing had limited negative predictive value as four llamas that were subsequently confirmed as infected were not detected using this assay. [ABSTRACT FROM AUTHOR]

Background: Increasing rates of cannabis use among emerging adults is a growing public health problem. Intensive longitudinal data can provide information on proximal motives for cannabis use, which can inform interventions to reduce use among emerging adults.Method: As part of a larger longitudinal study, patients aged 18-25 years (N=95) recruited from an urban Emergency Department completed daily text message assessments of risk behaviors for 28days, including daily cannabis quantity and motives. Using a mixed effects linear regression model, we examined the relationships between daily quantity of cannabis consumed and motives (i.e., enhancement, social, conformity, coping, and expansion).Results: Participants were, on average, 22.0 years old (SD=2.2); 48.4% were male, 45.3% were African American, and 56.8% received public assistance. Results from the multi-level analysis (clustering day within individual), controlling for gender, race, and receipt of public assistance, indicated daily use of cannabis use for enhancement (β=0.27), coping (β=0.15), and/or social motives (β=0.34) was significantly associated with higher quantities of daily cannabis use; whereas expansion and conformity motives were not.Conclusions: Daily data show that emerging adults who use cannabis for enhancement, social, and coping motives reported using greater quantities of cannabis. Future research should examine more comprehensive cannabis motives (e.g., boredom, social anxiety, sleep) and test tailored interventions focusing on alternative cognitive/behavioral strategies to address cannabis motives. [ABSTRACT FROM AUTHOR]

• Conducted latent profile analyses of emerging adults' social media use. • Distinguished screen time from engagement and general from alcohol-related. • Various forms of engagement seem to matter more than screen time. • The highest active engagers online might be the most at-risk for alcohol misuse. Nearly all U.S. emerging adults use social media at least daily, and most discuss their offline activities online, including their alcohol misuse. As a result, developing evidence finds a correlation between social media use and offline alcohol drinking, suggesting that social media may be a novel risk factor for alcohol misuse. However, there are conflicting findings about what specific function of social media use is risker – does the amount of time spent online or the types of online activities matter more? Our multidisciplinary team of human–computer interactionists, social workers, and public health scholars aimed to refine our understanding of the association between emerging adult social media use and alcohol misuse. To do so, we conceptualized social media use as a multidimensional construct, examining how much time emerging adults spend online (i.e., screen time) and their different online activities (i.e., social media engagement , such as posting pictures or reacting to posted content [e.g., liking shared pictures]). Taking this conceptualization a step further, we distinguished general online activities (i.e., general social media engagement , such as sharing pictures of food) from those explicitly related to offline alcohol consumption (i.e., alcohol-related social media engagement , such as sharing a video of someone drinking alcohol at a party). Finally, we examined if different levels of these three conceptualizations of social media use were risk factors for alcohol misuse and related negative consequences. We collected survey data from 249 emerging adults on Amazon Mechanical Turk. Using latent profile analyses, we attempted to distinguish the different ways we conceptualized social media use (i.e., screen time from general social media engagement and alcohol-related social media engagement.) We then examined whether significant differences existed between identified profiles and various alcohol-related outcomes in a typical and heavy drinking week. We identified 3-profile solutions for both screen time (low, medium, and high) and general social media engagement (minimum, moderate, and high) and a 2-profile solution for alcohol-related social media engagement (minimal and moderate). When we assessed for alcohol risk, screen time was not related to drinking at all (neither frequency nor quantity), not even for emerging adults who reported using social media almost constantly. However, during a heavy drinking week, those who moderately post alcohol-related content online drank more heavily and had more binge drinking days. Notably, and contrary to previous research, emerging adults who reported high general social media engagement were most at risk for binge drinking and experiencing more alcohol-related negative consequences. Findings underscore the importance of considering various forms of social media engagement – and not screen time – when studying the harms associated with using social media, including offline risk-taking behaviors like alcohol misuse. Results indicate that research, interventions, and clinical practice that target and treat emerging adult alcohol misuse should assess their social media behavior, concentrating on their engagement. This is especially true for the highest general engaging emerging adults who almost constantly post, respond, and react while online; these individuals might be the most at-risk and need support. [ABSTRACT FROM AUTHOR]

We examined relationships among personality (i.e., negative affectivity and conscientiousness), and use of licit and illicit substances in a sample of 421 college-aged social drinkers (52.7% women, 47.3% men). Results indicated significant relationships between personality and substance use as well as gender differences. Negative affectivity was related to greater illicit substance use, but not alcohol use or smoking. Conscientiousness was related to less alcohol use and smoking, which fully mediated relationships between conscientiousness and with less use of marijuana and other illicit substances. For women, conscientiousness was associated with less alcohol and smoking, compared to men. For men, alcohol use and smoking were more likely to lead to marijuana use, compared to women. Our findings support differential pathways from personality to substance use, and gender appears to be an important moderating factor. [Copyright &y& Elsevier]

Theoretical approaches to alcohol and violence have emphasized three interrelated domains of influence: the situational context, aggression-facilitating characteristics of individuals, and the impact of alcohol consumption. We examined these three domains as predictors of experiencing violence in the barroom setting. Participants were recruited through one of two phone surveys or through newspaper advertisements and classified into one of three groups: Experienced Bar Violence (EBV), Observed Bar Violence (OBV), and No Bar Violence (NBV). They completed questionnaires assessing individual difference and alcohol use variables, and an interview that assessed characteristics of their usual bar. The results suggested that individual difference and alcohol variables distinguished men in the EBV group from men in the OBV and NBV groups. However, women in the EBV group were distinguished from women in the NBV group by the characteristics of their usual bar and by the alcohol variables, but were distinguished from the OBV group only in terms of individual difference variables. The implications of these findings with respect to the influence of alcohol on barroom violence are discussed. [Copyright &y& Elsevier]

Focuses on the validation of experimental results and modelling data on the effect of temperature differences on a sample of vacuum glazing, which resulted in the differential expansion of one glass sheet relative to the other. Consistency of vacuum glazing; Occurrence of tensile and compressive stresses in the glass sheets; Discussion on the physical origins of these stresses and deflections; Deposition of the solder glass.

Several theories posit that cannabis and other substances are used to reduce negative affect. This daily report study considered whether variations in positive and negative affect, reported each morning, contributed to the likelihood of cannabis use later that day. We also explored whether levels of positive and negative affect reported immediately after cannabis use improved, relative to that day's morning levels. The sample included 183 men and 183 women representing heterosexual, cannabis-using couples from the community. Participants made independent, daily reports of affect and cannabis use episodes for 30 consecutive days. Using multilevel modeling, we modeled men's and women's use of cannabis on a given day as a function of morning levels of positive, hostile, and anxious affect, accounting for partner cannabis use that day, and mean levels of positive and negative affect. Men and women were more likely to use cannabis on a given day when morning positive affect was lower than typical for the person and when partner used cannabis that day. Neither hostile nor anxious affect contributed to later use of cannabis. Immediately after cannabis use, positive affect increased, and hostile and anxious affect decreased relative to that day's morning levels. The improved affect immediately after use suggests a mechanism of positive reinforcement. [ABSTRACT FROM AUTHOR]

Identifying as a 'smoker' has been associated with many cigarette smoking-related behaviors, including less frequent and intense cigarette use. Additional smoking behaviors (e.g., use of cannabis or cigars) also may contribute to self-identification as a 'smoker'. This study compared correlates of identifying as a 'smoker' and measurement strategies for non-daily cigarette consumption among young-adult intermittent and light daily smokers. Using data from Wave 1 of the PATH Study, different measurements of past 30-day non-daily cigarette use were evaluated. Weighted logistic regression models were used to compare associations with self-identification as a smoker among 18-24 year-old intermittent and light daily smokers (n = 1531). Use of other smoked products (combustible tobacco, cannabis) and other documented correlates of smoker identity were evaluated. As frequency of monthly smoking increased, self-identification as a smoker increased (1-5 days = 24%, 6-19 days = 48%, 20-29 days = 78%, light daily smokers = 93%, daily smokers using >5 cigarettes per day = 99%). Self-reported smoking status 12 months ago significantly contributed to current identification as a smoker. Smoking cigars daily or using cannabis in the past 30 days were each positively associated with smoker identity. Different measurement approaches to non-daily cigarette use offer different advantages in terms of interpretability and granularity of information. Compared to daily smokers, non-daily smokers exhibit significant variability in identifying as a smoker, and systematic correlates of smoker identification are apparent. These findings may serve to enhance understanding of non-daily smokers and potential targets for intervention among this growing subpopulation of tobacco users. [ABSTRACT FROM AUTHOR]

Background: Loeys-Dietz syndrome (LDS) is a congenital multisystem disorder affecting the cardiovascular and musculoskeletal system. Limited data have reported neurodevelopmental (ND) issues in LDS.Aims: To determine the extent of ND issues in patients with LDS.Methods: A prospective study was performed of LDS patients or their caregivers. The study included data collected via an online survey of age-specific questions. Standard statistical methods were used for baseline and demographic characteristics, as well as group comparisons.Outcomes: Data were obtained from 67 patients with LDS (54% female). Median age was 14.9 years. Gene mutations included TGFBR1 (39%), TGFBR2 (40%), SMAD3 (7%), and unknown (14%). Motor delays (30%, 18/61) and hypotonia (63%, 37/60) occurred frequently. Physical (62%, 39/62), occupational (41%, 23/56), and speech therapies (34%, 20/58) were common. Feeding issues were common (41%, 23/56). TGFBR1 mutations were more frequent among those with motor delays and feeding issues.Conclusions: Patients with LDS and/or their caregivers report at least one ND problem in most cases, and many require therapies. These data suggest ND disorders should be considered to be part of the phenotype. [ABSTRACT FROM AUTHOR]

Objectives: Drugged driving [DD] is a public health concern, particularly among emerging adults who have the highest rates of drug use. Understanding involvement with DD could inform prevention efforts for this population. We evaluated the prevalence of, motives for, and correlates of past-year DD among emerging adults from an urban, under-resourced community.Methods: Emerging adults (N=586) ages 18-25years (54% male, 56% African American, 34% European American) seeking care in an urban emergency department completed past-year surveys of demographics, frequency of DD within 4h of substance use, reasons for DD, and substance use.Results: DD was reported by 24% of participants (with 25% of those engaging in high frequency DD). DD after cannabis use was most common (96%), followed by prescription opioids, sedatives, and stimulants (9%-19%). Common reasons for DD were: needing to go home (67%), not thinking drugs affected driving ability (44%), not having to drive far (33%), and not feeling high (32%). Demographics were not associated with DD, but, as expected, those with DD had riskier substance use.Conclusions: In this clinical sample, using a conservative measure, DD, particularly following cannabis use, was relatively common among emerging adults. Based on these data, clinical interventions for cannabis and other drug use should include content on prevention of DD, with particular attention to motives such as planning ahead for alternatives to get home safely and weighing benefits and risks of DD. [ABSTRACT FROM AUTHOR]

Background: The past decade has seen over a four-fold increase in deaths from opioid overdose in the United States. To address this growing epidemic, many localities initiated policies to expand access to naloxone (a drug that reverses the effects of opioids); however, little is known how naloxone access affects opioid use behaviours.Methods: The present qualitative study used semi-structured, in-depth interviews with inpatients at a substance use treatment centre. All patients who met study inclusion criteria (in treatment for opioid use, between the ages of 18 and 40, able to speak and understand English, and had not previously completed an interview with the research team) were invited to participate. Interviews were conducted until thematic saturation was reached (N=20) and covered the participant's naloxone knowledge, access, and attitudes, as well as experience(s) with opioid use and opioid overdose, and their naloxone use in the context of opioid overdose. Thematic content analysis was used to analyze interview transcripts.Results: Five main themes were uncovered during analysis; first, awareness about naloxone, including, content knowledge and source information for naloxone. Naloxone awareness was very common among opioid users; however, depth of knowledge varied; some participants did not make any efforts to have naloxone available, and others felt that it was "just as important as a clean needle." The second theme explored how naloxone access intersects with drug selling. The third theme explored naloxone availability while using, including attitudes about naloxone, occasions with no naloxone availability, when naloxone is "good to have," and when naloxone is a priority for users. The fourth theme examined changes in opioid use behaviours associated with naloxone access. Primarily, participants discussed changing how much heroin they used in a given situation to achieve a bigger high. The final theme explored naloxone behaviours that alter overdose mortality risk, such as how users distinguish when to use naloxone, dis-incentives to naloxone use, and solo opioid use.Conclusion: Results indicate that though naloxone awareness was high, there was great variation in the associated attitudes and practices. Participants generally described naloxone as an important resource, but not all were inclined to carry or use it appropriately. Future research needs to examine why different groups of opioid users access naloxone differently, particularly to identify those at risk for experimental opioid use while carrying naloxone. [ABSTRACT FROM AUTHOR]

Studies of youth social media use (SMU) often focus on its frequency, measuring how much time they spend online. While informative, this perspective is only one way of viewing SMU. Consistent with uses and gratification theory, another is to consider how youth spend their time online (i.e., degree of engagement). We conducted latent profile analyses of survey data from 249 U.S. emerging adults (ages 18–26) to explore their SMU in terms of frequency and engagement. We derived separate 3-profile solutions for both frequency and engagement. High frequency social media users tended to be women and to have more Facebook friends. Highly engaged users (i.e., those most interactive online) tended to be White and more highly educated. Findings from this exploratory study indicate that youth SMU frequency and SMU engagement warrant separate consideration. As SMU becomes more ingrained into the fabric of daily life, it is conceivable that engagement may be a more meaningful way to assess youth SMU, especially in relation to the digital divide, since it can be used to meet important needs, including social interaction, information exchange, and self-expression. [ABSTRACT FROM AUTHOR]

Purpose: Cannabis use is common among emerging adults (ages 18-25), yet few prevention interventions have targeted this unique developmental period. Physical activity (PA) is an under-utilized intervention target for cannabis use, despite research showing its potential utility. Based on prior promising social media-delivered interventions targeting cannabis and PA separately, we developed and piloted, in a randomized controlled feasibility trial (NCT04901910), interventions for emerging adults who use cannabis that focused on PA.Procedures: Using social media, we recruited 60 emerging adults (Mean age=21.7 years; 63.3% female sex) who used cannabis (>=3 times/week for the past month) and could engage in PA. We randomized participants into one of 3 conditions (PA-Only; PA+Cannabis, Attention-Control) that each lasted 8 weeks and were delivered in secret Facebook groups by health coaches. We collected follow-up data at 3- and 6-months post-group start. Outcomes are presented descriptively given the pilot nature and limited sample size.Results: The interventions were rated favorably, with ratings of the content in each condition averaging around 3 on a 5-point scale. Both intervention groups demonstrated larger reductions in cannabis consequences and cannabis-impaired driving over time than the control condition. Findings were mixed regarding patterns of change in cannabis use in the intervention conditions. Proportions of group members reporting increased PA ranged from 38.9% to 80.0% across time.Conclusions: Interventions targeting PA and delivered via social media to emerging adults who regularly use cannabis offer a novel intervention target. These interventions warrant future investigation in larger trials over a longer follow-up period. [ABSTRACT FROM AUTHOR]

Mixed phase, hydrogenated amorphous and nanocrystalline silicon thin films grown by co-deposition (nanocrystals and amorphous material deposited sequentially in the same vacuum system) demonstrate pronounced quantum confinement effects. Based on photoluminescence measurements of co-deposited samples, we find evidence that the optical gap of nanocrystals embedded in hydrogenated amorphous silicon is increased to energies exceeding bulk crystalline silicon values -- at least as high as 1.35 eV. The broad spectrum of emission of the nanocrystals is attributed to the size distribution and local fluctuations in matrix hydrogenation. The temperature dependence of this PL suggests that these nanocrystals possess fewer defects than those grown by conventional plasma enhanced chemical vapor deposition methods. Interactions between electronic states in nanocrystals and localized states in amorphous silicon matrix tissues are discussed in terms of their role in determining the strength of the quantum confinement potential. [ABSTRACT FROM AUTHOR]

Abstract: With the growing interest in flexible electronics and the increased utilization of Indium Tin Oxide electrodes for display and photovoltaic applications the need for new materials is emerging. In this work we present the electro-optical properties of Ag nanowire networks as an alternative transparent conductive material. A comparison of different film deposition techniques is made and indicates that the properties of the network are independent of the fabrication method. Analysis of the electrical behavior as a function of nanowire density is made and compared with theoretical results as well as Monte Carlo simulations. Thermal annealing is shown to reduce the sheet resistance from 1000Ω/sq to 8Ω/sq; this reduction is achieved by local sintering of the nanowire junctions. Experimental optimization of Ag nanowire electrodes was undertaken and a peak in the electro-optical properties is observed at approximately 100mg/m². Finally a discussion of the potential integration of Ag nanowire networks into solar cells is undertaken; we observe that these electrodes show promise as an emerging transparent conductive material, especially for flexible applications. [Copyright &y& Elsevier]

Abstract: Background: Previous laboratory-based research suggests that withdrawal from marijuana may cause increased aggression. It is unclear whether this finding extends beyond the laboratory setting to the general population of marijuana users. The purpose of this study was to test a cross-sectional association between marijuana withdrawal symptoms and aggression among a representative sample of U.S. adult marijuana users, and to test whether this association was moderated by previous history of aggression. Methods: Data were analyzed from the National Epidemiologic Survey on Alcohol and Related Conditions. Wave Two data (2004–2005) were used for all variables except for history of aggression, which was assessed during the Wave One interview (2001–2002). Two outcomes were examined: self-report general aggression and relationship aggression. Odds ratios for aggression based on withdrawal symptoms and the interaction between withdrawal symptoms and history of aggression were calculated using logistic regression, adjusting for covariates and accounting for the complex survey design. Results: Among marijuana users with a history of aggression, marijuana withdrawal was associated with approximately 60% higher odds of past year relationship aggression (p <0.05). There was no association between withdrawal symptoms and relationship aggression among those without a history of aggression, and no association with general aggression regardless of history of aggression. Conclusions: The findings from this study support the notion that laboratory-based increases in aggression due to marijuana withdrawal extend to the general population of marijuana users who have a previous history of aggression. [Copyright &y& Elsevier]

Abstract: The result of experimental and numerical study that was undertaken to determine the performance characteristics of viscous flow turbines is presented. It is anticipated that these devices may find use in applications such as small power sources for electronic appliances and micro-combined heat and power applications. In the numerical work that was carried out to broaden the experimental results, commercial CFD solver Fluent 6.2 was used while accompanying software, Gambit 3.2, was used for performing the necessary pre-processing. The results of the experimental study indicate that the adiabatic efficiency of these machines is around 25%. The main reasons for the low efficiency have been identified to be, parasitic losses in the bearing, viscous losses in the end walls, and other dissipative losses in the plenum chamber that also significantly contribute to the low efficiencies of these devices. If these parasitic losses can be minimised the turbine could potentially operate with an adiabatic expansion efficiency close to the theoretical limit of around 40%. [Copyright &y& Elsevier]

Abstract: Computational fluid dynamics (CFD) studies of airflow in a digital reference model of the 17-generation airway (bronchial tree) were accomplished using the FLUENT® computational code, based on the anatomical model by Schmidt et al. [2004. A digital reference model of the human bronchial tree. Computerized Medical Imaging and Graphics 28, 203–211]. The lung model consists of 6.744×106 unstructured tetrahedral computational cells. A steady-state airflow rate of 28.3L/min was used to simulate the transient turbulent flow regime using a large eddy simulation (LES) turbulence model. This CFD mesh represents the anatomically realistic asymmetrical branching pattern of the larger airways. It is demonstrated that the nature of the secondary vortical flows, which develop in such asymmetric airways, varies with the specific anatomical characteristics of the branching conduits. [Copyright &y& Elsevier]

Abstract: Mars is a compelling astrobiological target, and a human mission would provide an opportunity to collect immense amounts of scientific data. Exploration alone, however, cannot justify the increased risk. Instead, three factors drive a human mission: economics, education, and exploration. A human mission has a unique potential to inspire the next generation of young people to enter critically needed science and engineering disciplines. A mission is economically feasible, and the research and development program put in place for a human mission would propel growth in related high-technology industries. The main hurdles are human physiological responses to 1–2 years of radiation and microgravity exposure. However, enabling technologies are sufficiently mature in these areas that they can be developed within a few decade timescale. Hence, the decision of whether or not to undertake a human mission to Mars is a political decision, and thus, educational and economic benefits are the crucial factors. [Copyright &y& Elsevier]

Abstract: Cobalt is not classified as an essential element for plants, however, it is usually described as “beneficial”. This trace element can be a contaminant in soils due to agricultural additives or metal refineries. Certain plants species have the ability to extract metals (such as Co) from soils, thus, cleaning the environment. Therefore, knowledge of the physiological mechanisms of metal absorption is required to improve these phytoremediation technologies. Patterns of cobalt accumulation and storage were determined in tomato (Lycopersicon esculentum) and wheat (Triticum aestivum) species. Plants were grown in nutrient solutions, with different Co treatments, using controlled environmental conditions. The spatial distributions of K, Ca, Fe and Co in whole plants, and in leaf and stem sections, were examined by micro-PIXE. In conjunction, total Co concentrations were determined by ICP-MS. Micro-PIXE spectroscopy proved to be a convenient technique for indicating Co concentrations and distribution patterns in these plants. This knowledge aids in the identification of vegetal Co sequestration and, thus, helps to unravel how Co is transported in higher plants. [Copyright &y& Elsevier]

Aims: This research investigates the relationship between dyslexia traits and nurse performance on a laboratory task designed to assess one of the key cognitive skills involved in drug administration. The potential moderating role of perceived performance control was also assessed, based on previous work demonstrating the importance of self-belief as a facilitator of vocational success. Background: Dyslexia within the health care professions has been the subject of wide and emotionally charged debate but has not yet been scientifically examined. Those who fear clinicians with dyslexia do so because of a presumed or potential risk to patient health and safety posed by dyslexia-induced performance error (e.g. problems with drug administration). Design, sample and methods: 46 nurses (40 student nurses and 6 qualified nurses) volunteered to complete a battery of computerised tasks assessing for dyslexia traits (using four accuracy tasks measuring different types of literacy skill), a paired association task designed to measure one of the key cognitive skills involved in drug administration) and a self-report questionnaire (Learning Styles Questionnaire, self-reported reading difficulty and a history of educational support, perceived control over performance). The performance criterion measure was constructed after detailed job analysis (involving analysis of official documentation, in-depth interviews and field observation across a variety of clinical settings) and involved matching drug names to patient names and vice versa. Results: The results showed that the dyslexia indicators (objective and self-report) were significantly correlated with performance on the paired association task. Contrary to expectation however, the perceived control variable was not associated with performance. Conclusion: The findings provide tentative support for the idea that some tasks might be problematic for the clinician with dyslexia. Taken in isolation however, it would be inappropriate to conclude that this will necessarily translate into true performance errors without taking into consideration the entire performance context. Suggestions are made for replicating and extending the study to provide a more solid and constructive basis for intervention (e.g. support measures, a built-in checking process). [ABSTRACT FROM AUTHOR]