Intact attentional control of working memory encoding in schizophrenia.

This study reports evidence that individuals with schizophrenia (SC) demonstrate intact attentional selection for visual working memory (WM) storage. A group of 62 participants with SC and 55 control participants without SC were studied in a series of 5 experiments that examined the ability to use top-down and bottom-up cues to guide WM encoding, as well as the ability to spontaneously select a subset of representations for storage. Participants with SC exhibited a consistent and robust ability to use selective attention in the control of WM in all 5 experiments, demonstrating a remarkable island of preserved functioning given the broad spectrum of impairments of attention and WM that have been widely reported in those with SC. These findings indicate that attention is not globally impaired in SC and make it possible to delineate more precisely the nature of the specific impairment of attention in this disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Does solitary substance use increase adolescents' risk for poor psychosocial and behavioral outcomes? A 9-year longitudinal study comparing solitary and social users.

This longitudinal study compared Grade 8 solitary cigarette smokers (n = 541), drinkers (n = 577), and marijuana users (n = 148) with adolescents who restricted their use of these substances to social settings (ns = 562, 1,426, and 388, respectively) on adolescent functioning and young adult outcomes. In Grade 8, solitary users held more positive beliefs about the consequences of substance use, earned poorer grades, engaged in more deviant behavior, and devoted less time to school and more time to social activities. By age 23, these solitary users had lower educational attainment, poorer self-rated health, and greater substance use problems. Results indicate the importance of better understanding and addressing the needs of this understudied group of high-risk youth. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

“双重授权”的开源新模式

开源并不是一个新观念。科学界从根本上看就是以这种观念为基础的,他们为了促进科学发展,公开共享最重要的信息。科学进步之所以能达到今天这样的速度,就是因为信息能够在全世界的科学家之间共享,他们共同参与测试、验证和改进工作。科学家们极少从头开始、而是以以前的发现和研究为基础进行新的探索,继续做出改进和完善。如果没有前人的工作,每隔一段时间就出现的那些重大科学突破是不可能发生的。与此相同的模式在软件开发领域也存在。这个领域的“科学家”是软件开发人员,他们的主要工作是利用像Qt这样的工具来开发软件代码。从微波炉到…     

On-line separation and determination of bromate in drinking waters using flow injection ICP mass spectrometry

A flow injection (FI) system with a microcolumn of anion exchanger has been used to effect rapid on-line separation of bromate and bromide prior to quantitation by ICP mass spectrometry. Basic performance studies are described including the effect of key FI parameters, i.e., sample injection volume, carrier stream flow rate, and eluent concentration on system response. The new approach permitted ultratrace determinations of bromate in drinking waters, the main benefits being low limit of detection (0.13 microg/L based on a 500-microL sample injection), rapid analysis time (10 min/sample), and good precision (2.8% at the 5 microg/L level). Accuracy was checked via an EC-sponsored interlaboratory trial.     

Isotopic analysis of uranium in tree bark by ICP mass spectrometry: a strategy for assessment of airborne contamination

Isotopic analysis of uranium in tree bark by ICP mass spectrometry is proposed as a new measurement strategy for monitoring airborne contamination and for discrimination of nuclear and nonnuclear emission sources. A quadrupole-based ICP mass spectrometer equipped with a microconcentric nebulizer and membrane desolvator was used to provide high-sensitivity measurement. The limit of detection for uranium (238U) was 0.004 ng L(-1). Measurement precision (235U/238U) was between 0.2 and 0.5% RSD for isotopic SRMs (U005 and U015; concentration, 1 microg L(-1)) and ranged from 0.4 to 3.1% RSD for tree bark extracts (U concentration, 0.03-0.08 microg L(-1)). Bark samples collected from the Peak District National Park in Derbyshire (U.K.) exhibited a natural 235U/238U isotope ratio value (0.0072) whereas samples from Sellafield, West Cumbria (U.K.) showed depletion in 235U (235U/238U = 0.0053-0.0064).     

Chemical Defenses Against Fish Predation in Three Brazilian Octocorals: 11β,12β-Epoxypukalide as a Feeding Deterrent in Phyllogorgia dilatata

The feeding-deterrence properties of crude extracts of three Brazilian octocoral species, Neospongodes atlantica Kükenthal (Alcyonacea, Nephtheidae), Plexaurella regia Castro (Gorgonacea, Plexauridae), and Phyllogorgia dilatata Esper (Gorgonacea, Gorgoniidae), were investigated. All the extracts were incorporated into food strips at the concentrations occurring in the living organisms. Crude extract and its ethyl acetate fraction obtained from P. dilatata collected in Armação dos Búzios (Rio de Janeiro State), when incorporated into artificial diets and tested in the habitat of origin, reduced consumption of food strips by fishes, relative to controls. Crude extracts from two octocoral species collected at the National Marine Park of Abrolhos (Bahia State), N. atlantica and P. regia, had no apparent feeding-deterrence properties; in fact, they seemed to stimulate feeding. Bioassay-guided fractionation of the bioactive P. dilatata crude extract revealed that the deterrent property was restricted to a medium polarity fraction. Field palatability experiments with two pure compounds isolated from this fraction revealed that the furanocembranolide 11,12-epoxypukalide is a potent feeding deterrent produced by P. dilatata against fish. Apparently, furanocembranolides are a particular class of compounds with feeding deterrent properties, protecting some octocorals from potential fish predator species in both tropical and temperate environments.     

Challenges and solutions for recruiting pregnant smokers into a nicotine replacement therapy trial.

Improvements in smoking cessation interventions for pregnant smokers are needed. One major step is to examine the potential effectiveness of nicotine replacement therapy (NRT). The potential benefits of providing pregnant women with NRT to help them quit smoking are still unknown; early interventions to test the effectiveness and efficacy are vital to advancing the field. This paper describes recruitment efforts for a multiclinic trial to test the effectiveness of NRT use in addition to behavioral therapy in promoting cessation during pregnancy. The biggest challenge is recruiting sufficient numbers of pregnant women. This paper discusses specific obstacles for recruitment and solutions. Knowing the potential pitfalls to recruiting pregnant women into these trials can lead to better studies and thus improved outcomes.     

Attenuation of cocaine-induced locomotor activity by butyrylcholinesterase.

A primary enzyme for the metabolism of cocaine is butyrylcholinesterase (BChE). To determine whether the systemic administration of BChE can increase the metabolism of cocaine sufficiently to alter a behavioral effect, rats were tested in a locomotor activity chamber after receiving 17 mg of cocaine per kg intraperitoneally. In rats pretreated intravenously with 5,000 IU of horse serum-derived BChE, the locomotor activity effect was significantly attenuated. BChE pretreatment increased plasma BChE levels approximately 400-fold. When added to rat plasma, this amount of BChE reduced the cocaine half-life from over 5 hr to less than 5 min. BChE altered the cocaine metabolic pattern such that the relatively nontoxic metabolite ecgonine methyl ester was produced, rather than benzoylecgonine. These results suggest that systemic administration of BChE can increase the metabolism of cocaine sufficiently to alter a behavioral effect of cocaine and thus should be investigated as a potential treatment for cocaine abuse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Is halo error a property of the rater, ratees, or the specific behaviors observed?

The stability of halo errors when the ratees, the specific behavioral episodes observed, or both varied was studied. In a laboratory study, halo errors were highly unstable when either the ratees or the ratee behaviors varied (average stability coefficients were .20 and .18 when ratee behavior or both ratees and their behavior varied, respectively), but halo errors were moderately stable when the ratees and the specific performance segments viewed were kept constant. In a field study using actual teacher ratings in which the ratee, the ratee's role, or the semester in which ratings were obtained was varied, very low stability coefficients were again found. The results suggest that halo error is not a stable characteristic of the rater or the ratees but rather is partly a characteristic of the unique rating situation. Practical and theoretical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relationship formation and relational control as correlates of psychotherapy quality and outcome.

This study examined the nature of therapist–client interactions within and across seven psychotherapy cases (a) to test whether therapeutic outcome is a function of a transition from relational incongruence to relational congruence (S. Strong, 1982), and (b) to investigate the relation of relational congruence and control to qualitative aspects of the therapy relationship and to therapy outcome. Measures of therapist and client response patterning served as indices of relational congruence and of relational control. Relationship quality was assessed in terms of therapist and client ratings of their working alliance and of therapy session depth and smoothness. Outcome was operationalized in terms of symptom reduction. Results showed limited support for a relationship between relational congruence and therapy outcome and suggested that relational control is not a significant factor in client or therapist evaluations of relationship quality or therapy outcome. (PsycINFO Database Record (c) 2010 APA, all rights reserved)