Young Adults, Social Networks, and Addiction Recovery: Post Treatment Changes in Social Ties and Their Role as a Mediator of 12-Step Participation

Background: Social factors play a key role in addiction recovery. Research with adults indicates individuals with substance use disorder (SUD) benefit from mutual-help organizations (MHOs), such as Alcoholics Anonymous, via their ability to facilitate adaptive network changes. Given the lower prevalence of sobriety-conducive, and sobriety-supportive, social contexts in the general population during the life-stage of young adulthood, however, 12-step MHOs may play an even more crucial recovery-supportive social role for young adults, but have not been investigated. Greater knowledge could enhance understanding of recovery-related change and inform young adults’ continuing care recommendations. Methods: Emerging adults (N = 302; 18–24 yrs; 26% female; 95% White) enrolled in a study of residential treatment effectiveness were assessed at intake, 1, 3, 6, and 12 months on 12-step attendance, peer network variables (“high [relapse] risk” and “low [relapse] risk” friends), and treatment outcomes (Percent Days Abstinent; Percent Days Heavy Drinking). Hierarchical linear models tested for change in social risk over time and lagged mediational analyses tested whether 12-step attendance conferred recovery benefits via change in social risk. Results: High-risk friends were common at treatment entry, but decreased during follow-up; low-risk friends increased. Contrary to predictions, while substantial recovery-supportive friend network changes were observed, this was unrelated to 12-step participation and, thus, not found to mediate its positive influence on outcome. Conclusions: Young adult 12-step participation confers recovery benefit; yet, while encouraging social network change, 12-step MHOs may be less able to provide social network change directly for young adults, perhaps because similar-aged peers are less common in MHOs. Findings highlight the importance of both social networks and 12-step MHOs and raise further questions as to how young adults benefit from 12-step MHOs

Improved Fast Randomized Iteration Approach to Full Configuration Interaction

We present three modifications to our recently introduced fast randomized iteration method for full configuration interaction (FCI-FRI) and investigate their effects on the method's performance for Ne, H$_2$O, and N$_2$. The initiator approximation, originally developed for full configuration interaction quantum Monte Carlo, significantly reduces statistical error in FCI-FRI when few samples are used in compression operations, enabling its application to larger chemical systems. The semi-stochastic extension, which involves exactly preserving a fixed subset of elements in each compression, improves statistical efficiency in some cases but reduces it in others. We also developed a new approach to sampling excitations that yields consistent improvements in statistical efficiency and reductions in computational cost. We discuss possible strategies based on our findings for improving the performance of stochastic quantum chemistry methods more generally.Comment: 13 pages, 5 figure

Approximating matrix eigenvalues by subspace iteration with repeated random sparsification

Traditional numerical methods for calculating matrix eigenvalues are prohibitively expensive for high-dimensional problems. Iterative random sparsification methods allow for the estimation of a single dominant eigenvalue at reduced cost by leveraging repeated random sampling and averaging. We present a general approach to extending such methods for the estimation of multiple eigenvalues and demonstrate its performance for several benchmark problems in quantum chemistry.Comment: 31 pages, 7 figure

The effect of frequent hemodialysis on nutrition and body composition: frequent Hemodialysis Network Trial.

We investigated the effects of frequency of hemodialysis on nutritional status by analyzing the data in the Frequent Hemodialysis Network Trial. We compared changes in albumin, body weight, and composition among 245 patients randomized to six or three times per week in-center hemodialysis (Daily Trial) and 87 patients randomized to six times per week nocturnal or three times per week conventional hemodialysis, performed largely at home (Nocturnal Trial). In the Daily Trial, there were no significant differences between groups in changes in serum albumin or the equilibrated protein catabolic rate by 12 months. There was a significant relative decrease in predialysis body weight of 1.5 ± 0.2 kg in the six times per week group at 1 month, but this significantly rebounded by 1.3 ± 0.5 kg over the remaining 11 months. Extracellular water (ECW) decreased in the six times per week compared with the three per week hemodialysis group. There were no significant between-group differences in phase angle, intracellular water, or body cell mass (BCM). In the Nocturnal Trial, there were no significant between-group differences in any study parameter. Any gain in 'dry' body weight corresponded to increased adiposity rather than muscle mass but was not statistically significant. Thus, frequent in-center hemodialysis reduced ECW but did not increase serum albumin or BCM while frequent nocturnal hemodialysis yielded no net effect on parameters of nutritional status or body composition

Non-O157 Shiga Toxin–Producing \u3ci\u3eEscherichia coli\u3c/i\u3e Infections in the United States, 1983–2002

Background. Shiga toxin–producing Escherichia coli (STEC) O157:H7 is a well-recognized cause of bloody diarrhea and hemolytic-uremic syndrome (HUS). Non-O157 STEC contribute to this burden of illness but have been underrecognized as a result of diagnostic limitations and inadequate surveillance. Methods. Between 1983 and 2002, 43 state public health laboratories submitted 940 human non-O157 STEC isolates from persons with sporadic illnesses to the Centers for Diseases Control and Prevention reference laboratory for confirmation and serotyping. Results. The most common serogroups were O26 (22%), O111 (16%), O103 (12%), O121 (8%), O45 (7%), and O145 (5%). Non-O157 STEC infections were most frequent during the summer and among young persons (median age, 12 years; interquartile range, 3–37 years). Virulence gene profiles were as follows: 61% stx1 but not stx2; 22% stx2 but not stx1; 17% both stx1 and stx2; 84% intimin (eae); and 86% enterohemolysin (E-hly). stx2 was strongly associated with an increased risk of HUS, and eae was strongly associated with an increased risk of bloody diarrhea. STEC O111 accounted for most cases of HUS and was also the cause of 3 of 7 non-O157 STEC outbreaks reported in the United States. Conclusions. Non-O157 STEC can cause severe illness that is comparable to the illness caused by STEC O157. Strains that produce Shiga toxin 2 are much more likely to cause HUS than are those that produce Shiga toxin 1 alone. Improving surveillance will more fully elucidate the incidence and pathological spectrum of these emerging agents. These efforts require increased clinical suspicion, improved clinical laboratory isolation, and continued serotyping of isolates in public health laboratories

The First Structure of an RNA m5C Methyltransferase, Fmu, Provides Insight into Catalytic Mechanism and Specific Binding of RNA Substrate

AbstractThe crystal structure of E. coli Fmu, determined at 1.65 Å resolution for the apoenzyme and 2.1 Å resolution in complex with AdoMet, is the first representative of the 5-methylcytosine RNA methyltransferase family that includes the human nucleolar proliferation-associated protein p120. Fmu contains three subdomains which share structural homology to DNA m5C methyltransferases and two RNA binding protein families. In the binary complex, the AdoMet cofactor is positioned within the active site near a novel arrangement of two conserved cysteines that function in cytosine methylation. The site is surrounded by a positively charged cleft large enough to bind its unique target stem loop within 16S rRNA. Docking of this stem loop RNA into the structure followed by molecular mechanics shows that the Fmu structure is consistent with binding to the folded RNA substrate

Valuing Transgenic Cotton Technologies Using a Risk/Return Framework

Stochastic Efficiency with Respect to a Function (SERF) is used to rank transgenic cotton technology groups and place an upper and lower bound on their value. Yield and production data from replicated plot experiments are used to build cumulative distribution functions of returns for nontransgenic, Roundup Ready, Bollgard, and stacked gene cotton cultivars. Analysis of Arkansas data indicated that the stacked gene and Roundup Ready technologies would be preferred by a large number of risk neutral and risk averse producers as long as the costs of the technology and seed are below the lower bounds calculated in this manuscript.cotton, financial risk, market value, SERF, transgenic, Agribusiness, Crop Production/Industries, Risk and Uncertainty, Q12, Q16,

Inhibition of Toll-Like Receptor 2-Mediated Interleukin-8 Production in Cystic Fibrosis Airway Epithelial Cells via the α7-Nicotinic Acetylcholine Receptor

Cystic Fibrosis (CF) is an inherited disorder characterised by chronic inflammation of the airways. The lung manifestations of CF include colonization with Pseudomonas aeruginosa and Staphylococcus aureus leading to neutrophil-dominated airway inflammation and tissue damage. Inflammation in the CF lung is initiated by microbial components which activate the innate immune response via Toll-like receptors (TLRs), increasing airway epithelial cell production of proinflammatory mediators such as the neutrophil chemokine interleukin-8 (IL-8). Thus modulation of TLR function represents a therapeutic approach for CF. Nicotine is a naturally occurring plant alkaloid. Although it is negatively associated with cigarette smoking and cardiovascular damage, nicotine also has anti-inflammatory properties. Here we investigate the inhibitory capacity of nicotine against TLR2- and TLR4-induced IL-8 production by CFTE29o- airway epithelial cells, determine the role of α7-nAChR (nicotinic acetylcholine receptor) in these events, and provide data to support the potential use of safe nicotine analogues as anti-inflammatories for CF