Abstinence-based incentives in methadone maintenance: Interaction with intake stimulant test results.

Baseline drug use detected in urine toxicology has been shown to predict drug abuse treatment outcome, including response to contingency management interventions with drug abstinence as their target. This study examined the association between baseline urine test result and treatment outcome in stabilized methadone maintenance patients with ongoing stimulant use to determine whether abstinence incentives were differentially effective in those testing stimulant negative versus positive at study entry. Participants were 386 methadone-maintained patients who took part in a National Drug Abuse Treatment Clinical Trials Network multisite study aimed at reducing stimulant abuse during treatment (J. M. Peirce et al., 2006). At study intake, 24% of participants tested stimulant negative and 76% tested positive. Those testing negative at entry submitted 82% negative urines during the study versus 36% for those testing positive at entry (odds ratio [OR] = 8.67; confidence interval [CI] = 5.81-12.94). Compared with those receiving usual care, the addition of abstinence incentives resulted in a significant increase in stimulant-negative urine samples submitted during the study both for those testing negative at study entry (OR = 2.27; CI = 1.13- 4.75) and for those testing positive (OR = 1.84; CI = 1.25-2.71). These findings suggest that abstinence incentives have significant clinical benefits independent of initial drug use severity among methadone maintenance patients with ongoing stimulant drug use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Numerical comparison of lattice unit cell designs for medical implants by additive manufacturing

The aim of this study was to compare traditional strut-based lattices with minimal surface designs using morphological analysis and image-based simulations of design files. While the two types have been studied widely, no direct comparison has ever been done. Surprisingly, there are no major differences in performance between the two types generally, but minimal surface designs do outperform slightly on angular load simulation. However, minimal surface designs in this density range are shown to have very thin walls, potentially making their accurate production more challenging, or more suitable for applications where larger pore sizes and sheet thicknesses may be applicable. Interesting results such as dual pore size distributions and variations in tortuosity of pore networks are demonstrated, with differences between various designs. The results show that all the tested designs are suitable for bone implants, but the best design might be selected based on its specialised performance requirements.     

Validation of a novel blinding method for measuring postoperative knee articular cartilage using magnetic resonance imaging

Magnetic Resonance Materials in Physics, Biology and Medicine - To test PEEK implant-associated MRI artifacts, a method for blinding MRI readers, the repeatability of cartilage thickness measures...     

Why is multiculturalism good?

This article explores the moral sources that give multiculturalism the potency to move psychology to reassess itself. The power of the multicultural perspective appears to derive from its ability to show how psychology's tendency toward monocultural universalism has undermined its aims as a science of human behavior and promoter of human welfare. The multicultural critique also draws on Euro-American moral traditions and ideals, such as individual rights, authenticity, respect, and tolerance. In spite of the importance of these ideals, multiculturalists often criticize Euro-American culture without acknowledging their debt to it. Moreover, these particularist moral sources undercut multiculturalism's universalist appeal. There is a paradoxical tendency among some advocates of multiculturalism to encourage cultural separatism and an inarticulateness in dealing with intercultural value conflict. We present some recommendations for dealing with these dilemmas from philosophical hermeneutics, including the contextualization of multiculturalism, an approach to sifting and evaluating cultural values, and an ontological account of the dialogical nature of humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessment of quality of life in a multicultural cancer patient population.

Quality of life (QOL) is increasingly assessed in cancer patients. In this article, the authors examined the psychometric performance of a commonly used QOL questionnaire, the Quality of Life Questionnaire--Cancer 30 (QLQ-C30; N. K. Aaronson et al., 1993), in multiethnic cancer patients. Content validation studies in patients and clinicians identified possible new items. Multiple-group confirmatory factor analysis supported equivalent structure across ethnic groups (Caucasians and Asian/Pacific Islanders [APIs]). A higher order QOL factor appeared to directly affect functioning scales and symptom count. Exploratory factor analysis examined effects of new items. Ten factors were extracted, 6 consistent with the original instrument and 4 reflecting potentially new aspects of QOL: Positive Social Support, Coping, Existential Well-Being, and Sexuality/Intimacy. The QLQ-C30 appears appropriate for use in API cancer patients. Further work needs to ensure that it includes all important domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Experimental demonstration of a two-phase population extinction hazard

Population extinction is a fundamental biological process with applications to ecology, epidemiology, immunology, conservation biology and genetics. Although a monotonic relationship between initial population size and mean extinction time is predicted by virtually all theoretical models, attempts at empirical demonstration have been equivocal. We suggest that this anomaly is best explained with reference to the transient properties of ensembles of populations. Specifically, we submit that under experimental conditions, many populations escape their initially vulnerable state to reach quasi-stationarity, where effects of initial conditions are erased. Thus, extinction of populations initialized far from quasi-stationarity may be exposed to a two-phase extinction hazard. An empirical prediction of this theory is that the fit Cox proportional hazards regression model for the observed survival time distribution of a group of populations will be shown to violate the proportional hazards assumption early in the experiment, but not at later times. We report results of two experiments with the cladoceran zooplankton Daphnia magna designed to exhibit this phenomenon. In one experiment, habitat size was also varied. Statistical analysis showed that in one of these experiments a transformation occurred so that very early in the experiment there existed a transient phase during which the extinction hazard was primarily owing to the initial population size, and that this was gradually replaced by a more stable quasi-stationary phase. In the second experiment, only habitat size unambiguously displayed an effect. Analysis of data pooled from both experiments suggests that the overall extinction time distribution in this system results from the mixture of extinctions during the initial rapid phase, during which the effects of initial population size can be considerable, and a longer quasi-stationary phase, during which only habitat size has an effect. These are the first results, to our knowledge, of a two-phase population extinction process.     

CONSUMPTION OF THE MOLECULAR OXYGEN IN POLYMERIZATION SYSTEMS USING PHOTOSENSITIZED OXIDATION OF DIMETHYLANTHRACENE

It is well known that the presence of oxygen in free radical polymerization systems leads to an inhibition period and a lowered ultimate conversion. In this contribution, we report a method for consuming molecular oxygen photochemically before the polymerization takes place, thereby allowing the reaction to proceed in an oxygen-free environment. The method is based on the generation of singlet oxygen by reaction of the ground state oxygen with the excited triplet state of the singlet oxygen generator (a porphyrin, Znttp). The singlet oxygen is then consumed by reaction with a second compound (the singlet oxygen trapper, dimethylanthracene). The possible factors that might affect the efficiency of the singlet oxygen generation/trapping processes were discussed and the effectiveness of a dimethylanthracene/Znttp combination for consumption of oxygen was investigated in two acrylate systems of different viscosity.     

Diel mercury-concentration variations in streams affected by mining and geothermal discharge

Diel variations of concentrations of unfiltered and filtered total Hg and filtered methyl Hg were documented during 24-h sampling episodes in water from Silver Creek, which drains a historical gold-mining district near Helena, Montana, and the Madison River, which drains the geothermal system of Yellowstone National Park. The concentrations of filtered methyl Hg had relatively large diel variations (increases of 68 and 93% from morning minima) in both streams. Unfiltered and filtered (0.1-microm filtration) total Hg in Silver Creek had diel concentration increases of 24% and 7%, respectively. In the Madison River, concentrations of unfiltered and filtered total Hg did not change during the sampling period. The concentration variation of unfiltered total Hg in Silver Creek followed the diel variation in suspended-particle concentration. The concentration variation of filtered total and methyl Hg followed the solar photocycle, with highest concentrations during the early afternoon and evening and lowest concentrations during the morning. None of the diel Hg variations correlated with diel variation in streamflow or major ion concentrations. The diel variation in filtered total Hg could have been produced by adsorption-desorption of Hg2+ or by reduction of Hg(II) to Hg0 and subsequent evasion of Hg0. The diel variation in filtered methyl Hg could have been produced by sunlight- and temperature-dependent methylation. This study is the first to examine diel Hg cycling in streams, and its results reinforce previous conclusions that diel trace-element cycling in streams is widespread but often not recognized and that parts of the biogeochemical Hg cycle respond quickly to the daily photocycle.     

Water drinking induced in sheep by angiotensin: A physiological or pharmacological effect?

The effect of val5-angiotensin II amide on water drinking in sheep was studied against a background of comprehensive data on arterial blood and cerebrospinal fluid angiotensin II levels in sheep under a variety of physiological conditions. 10 sheep of Corriedale or Merino breeds were used in Exp I and 4 in Exp II; 5 ewes were used in Exp III. Physiological range of blood angiotensin II concentration is 1-100 ng/100 ml. Intravenous infusion of angiotensin II within the physiological range did not increase water drinking. Intracarotid infusion of angiotensin II, or injection into 3rd ventricle or hypothalamus, consistently caused immediate drinking of large amounts of water. Dosages necessary for effect were in the supraphysiological range. Quantitative examination of data in sheep and other species suggests that a physiological role for angiotensin II in thirst is not proved. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)