Now or later? Striatum and insula activation to immediate versus delayed rewards.

Neuroimaging studies on delay discounting tasks that use reward delays ranging from minutes to days have implicated the insula and striatum in the processing of intertemporal decisions. This study aimed at assessing whether these brain regions would also be involved in decision-making when subjects have to wait through the delays within the range of seconds. Using functional MRI in 13 healthy volunteers, we repeatedly presented monetary options with delays that differed within the range of multiple seconds. Using a region-of-interest approach, we found significant activation in the bilateral anterior insula and striatum when subjects chose either the immediate (smaller) or delayed (larger) option. In particular, insular activation was observed after the response and the delay, when the outcome of the immediate or the delayed choice was shown. Significantly greater activation was observed in the ventroanterior striatum while subjects chose the immediate, as opposed to the delayed, options and also after receiving the outcome of waiting through the longer delay option. The evidence presented here indicates that both the ventral striatum and the insula are involved in the processing of choosing delay options as well as the consequences of choices with delays in the seconds' range. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Slow release polymer–iodine tablets for disinfection of untreated surface water

Simple water treatment devices are designed to treat small amounts of drinking water for home use. This study was undertaken to develop an iodine‐releasing polymeric formulation and examine its potential as a domestic water purifier for untreated surface water. The antimicrobial tablet formulation was made from gum arabic (GA), poly(vinylalcohol) (PVA), ethyl cellulose (EC), and poly(vinylpyrrolidone)‐iodine (PVP‐I). The formulation consisted of a dispersible core tablet surrounded by a hydrophilic coating of EC and poly(ethylene glycol) mixture. These stable, non‐vaporizing, and water‐insoluble tablets slowly release iodine through diffusion over 48 h when suspended in water. The swelling behavior and release were observed to be the functions of excipient composition, iodine loading, and coating materials. Iodine release was determined by UV–VIS spectroscopy and volumetric titrations. The tablets were also assessed for antimicrobial activity against Escherichia coli, Staphylococcus aureus, Listeria monocytogenes Scott A, and Salmonella typhimurium. The disinfection efficiency of the developed tablets was compared with a commercial formulation (Potable Aqua®) as both contain iodine‐releasing active compounds and work on the antimicrobial property of released iodine. The difference between the two formulations is that water‐dispersible Potable Aqua® has a higher amount of free iodine quickly available in water thereby making it a fast‐action emergency water purifier, whereas the developed water‐insoluble polymer–iodine tablets act slowly and require 24 h to show the same disinfection efficacy with lower content of iodine in water. Overnight release of iodine in water from polymer–iodine tablets was effective in 99.9% reduction of an initial cell count of ～ 10⁷ colony forming units (cfu)/mL. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Memory capacity, selective control, and value-directed remembering in children with and without attention-deficit/hyperactivity disorder (ADHD).

Objective: The ability to select what is important to remember, to attend to this information, and to recall high-value items leads to the efficient use of memory. The present study examined how children with and without attention-deficit/hyperactivity disorder (ADHD) performed on an incentive-based selectivity task in which to-be-remembered items were worth different point values. Method: Participants were 6–9 year old children with ADHD (n = 57) and without ADHD (n = 59). Using a selectivity task, participants studied words paired with point values and were asked to maximize their score, which was the overall value of the items they recalled. This task allows for measures of memory capacity and the ability to selectively remember high-value items. Results: Although there were no significant between-groups differences in the number of words recalled (memory capacity), children with ADHD were less selective than children in the control group in terms of the value of the items they recalled (control of memory). All children recalled more high-value items than low-value items and showed some learning with task experience, but children with ADHD Combined type did not efficiently maximize memory performance (as measured by a selectivity index) relative to children with ADHD Inattentive type and healthy controls, who did not differ significantly from one another. Conclusions: Children with ADHD Combined type exhibit impairments in the strategic and efficient encoding and recall of high-value items. The findings have implications for theories of memory dysfunction in childhood ADHD and the key role of metacognition, cognitive control, and value-directed remembering when considering the strategic use of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

High Activity Solid Base Catalysts for Alkenyl Aromatic Isomerisation

The isomerisation of allylbenzene, dimethoxyallylbenzene (4-allyl-1,2-dimethoxybenzene), eugenol (2-methoxy-4-(2-propenyl)phenol), and estragole (4-allylanisole) into their respective cis/trans internal alkenyl aromatics has been studied over a supported solid base catalysts (K₂CO₃/alumina). The catalyst was active at 305 K with conversions as high as 36%. However all reactants cause deactivation of the catalyst.     

Changes in self-control problems and attention problems during middle school predict alcohol, tobacco, and marijuana use during high school.

Although deficits in impulse control have been linked to adolescent use of alcohol and illicit drugs, less attention has been given to variability in change in impulse control across adolescence and whether this variability may be a signal of risk for early substance use. The goals of the current study were to examine growth in two aspects of impulse control, self-control problems and attention problems, across middle adolescence, and to test the prospective effects of level and change in these variables on levels and change over time in substance use. Data are from a community sample of 955 adolescents interviewed (along with their parents and teachers) annually from 6th to 11th grade. Results indicated that greater self-control problems and attentional problems in the 6th grade and increases in these problems over time were associated with higher levels of substance use at 11th grade. Our results suggest that modeling change over time enhances the understanding of how impulse control influences the development of substance use. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Cyclic Stretch Induces Inducible Nitric Oxide Synthase and Soluble Guanylate Cyclase in Pulmonary Artery Smooth Muscle Cells

In the pulmonary vasculature, mechanical forces such as cyclic stretch induce changes in vascular signaling, tone and remodeling. Nitric oxide is a potent regulator of soluble guanylate cyclase (sGC), which drives cGMP production, causing vasorelaxation. Pulmonary artery smooth muscle cells (PASMCs) express inducible nitric oxide synthase (iNOS), and while iNOS expression increases during late gestation, little is known about how cyclic stretch impacts this pathway. In this study, PASMC were subjected to cyclic stretch of 20% amplitude and frequency of 1 Hz for 24 h and compared to control cells maintained under static conditions. Cyclic stretch significantly increased cytosolic oxidative stress as compared to static cells (62.9 ± 5.9% vs. 33.3 ± 5.7% maximal oxidation), as measured by the intracellular redox sensor roGFP. Cyclic stretch also increased sGCβ protein expression (2.5 ± 0.9-fold), sGC activity (1.5 ± 0.2-fold) and cGMP levels (1.8 ± 0.2-fold), as well as iNOS mRNA and protein expression (3.0 ± 0.9 and 2.6 ± 0.7-fold, respectively) relative to control cells. An antioxidant, recombinant human superoxide dismutase (rhSOD), significantly decreased stretch-induced cytosolic oxidative stress, but did not block stretch-induced sGC activity. Inhibition of iNOS with 1400 W or an iNOS-specific siRNA inhibited stretch-induced sGC activity by 30% and 68% respectively vs. static controls. In conclusion, cyclic stretch increases sGC expression and activity in an iNOS-dependent manner in PASMC from fetal lambs. The mechanism that produces iNOS and sGC upregulation is not yet known, but we speculate these effects represent an early compensatory mechanism to counteract the effects of stretch-induced oxidative stress. A better understanding of the interplay between these two distinct pathways could provide key insights into future avenues to treat infants with pulmonary hypertension.     

Premature termination in couple therapy with veterans: Definitions and prediction of long-term outcomes.

Premature termination (PT) has been identified as widespread in individual, family, and couple therapy. Unfortunately, research on PT utilizes numerous definitions of PT without providing guidance on which definition may be most clinically useful. The current study investigated seven definitions of PT (three based on therapist ratings and four based on quantitative measures) utilizing a sample of 177 couples seeking treatment at two Department of Veterans Affairs medical centers. Results indicated that PT occurred in 50–80% of couples; however, agreement between the definitions of PT was generally only in the slight to fair range, making it difficult to determine whether a particular couple was ready to terminate treatment. Additionally, many commonly used definitions of PT were unrelated to level or maintenance of relationship functioning following treatment. In contrast, two definitions of PT (ending treatment in the distressed range and therapist-rated likelihood of future unhappiness) significantly predicted larger decreases in relationship satisfaction during the 18 months following therapy, as well as lower levels of satisfaction and relationship stability 18 months after termination. Additionally, long-term relationship functioning was especially poor when both these definitions of PT were met, suggesting that both qualitative and quantitative definitions should inform decisions about termination in couple therapy. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Conference Reviews

Abstract

The desire to teach in a way that acknowledges our position in the world as global citizens faces several challenges, many of which are global in nature. We identify three of these. First, there is the split between “modern” and “traditional” that can be found in a wide range of institutional and historical practices the world over. Second, there is the problem of language which has embedded within it certain historical presumptions. Third, there is the hesitancy in studio teaching to address issues that allow students to see themselves as actors in global history. What we advocate is a global critique of anti-global practices.