NMDA receptor antagonism impairs reversal learning in developing rats.

Four experiments examined the effect of dizocilpine maleate (MK-801), a noncompetitive N-methyl-Daspartate (NMDA) receptor antagonist, on reversal learning during development. On postnatal days (PND) 21, 26, or 30, rats were trained on spatial discrimination and reversal in a T-maze. When MK-801 was administered (intraperitoneally) before both acquisition and reversal, 0.18 mg/kg generally impaired performance, whereas doses of 0.06 mg/kg and 0.10 mg/kg, but not 0.03 mg/kg, selectively impaired reversal learning (Experiments 1 and 3). The selective effect on reversal was not a result of sensitization to the second dose of MK-801 (Experiment 2) and was observed when the drug was administered only during reversal in an experiment addressing state-dependent learning (Experiment 4). Spatial reversal learning is more sensitive to NMDA-receptor antagonism than is acquisition. No age differences in sensitivity to MK-801 were found between PND 21 and 30. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Smart Playing Cards: A Ubiquitous Computing Game

We present the ‘Smart Playing Cards’ application, a ubiquitous computing game that augments a classical card game with information technological functionality by attaching RFID tags to the cards. We also mention requirements that such an application makes on a supporting software infrastructure for ubiquitous computing. Correspondence to: Nr K. R?mer or Ms S. Domnitcheva, Department of Computer Science, ETH Zürich, 8092 Zürich, Switzerland. Email: roemer@inf.ethz.ch, or domnitch@ inf.ethz.ch     

Effects of Nutrient Source and Supply on Crude Oil Biodegradation in Continuous-Flow Beach Microcosms

Ammonium and nitrate were used as nitrogen sources to support microbial biodegradation of crude oil in continuous-flow beach microcosms to determine whether either nutrient was more effective in open systems, such as intertidal shorelines. No differences in the rate or extent of oil biodegradation were observed, regardless of whether these nutrients were provided continuously or intermittently. Nutrients were provided once every two weeks to intermittent-input microcosms and washed out within four to five days. In continuous-input microcosms, ammonium and nitrate were assimilated as quickly as they were provided during the first week, but both accumulated to greater than 10?mg?N/L thereafter. The sensitivity of the oil mineralization rate to nutrient input decreased rapidly as the extent of oil degradation increased, and after about two weeks the rate of oil-mineralization appeared to be independent of nutrient input. Therefore, there may be little value in maintaining a long-term supply of nutrients in contact with oil-contaminated sediments. The rates of microbial assimilation of ammonium and nitrate followed similar trends. Both compounds were assimilated more slowly as the extent of oil biodegradation increased, and the nitrate uptake rates approached zero after about two weeks. Ammonium assimilation continued at a low rate throughout the six-week experiment, but this did not appear to affect the rate of oil mineralization. Assimilation of ammonium resulted in a sharp decrease in the pH of the synthetic seawater that was pumped continuously through the microcosms, but nitrate had a much smaller effect on pH. The magnitude of the ammonium-associated pH change was never as large as was observed in previous studies involving oil biodegradation in batch reactors, however, and did not affect the oil-biodegradation rate.     

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.     

Evaluation of linguistic variations by college students with and without head injuries.

Evaluated the impact of spoken language on listeners by examining the effects of prior head injury, speech register, and active vs passive listening among 56 head-injured (HI) and 55 non-HI undergraduates. Ss rated the degree to which they liked the speaker and also the extent to which groups of negative and positive adjectives described the speaker. There were no differences between HI and non-HI Ss in how much they liked speakers using the normal register, but non-HI Ss liked the motherese speakers more than did HI Ss. Raters liked motherese speakers less when addressed directly than when they were not being directly addressed. Regardless of listener perspective, HI Ss liked motherese speakers less and rated them more negatively than non-HI Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Active site mutants of human herpesvirus-6 proteinase

OBJECTIVES: To assess the comparability of the Hybritech Tandem-R and Abbott AxSYM PSA assays in the setting of a hospital laboratory changing methods of PSA assay. METHODS: A total of 115 serum samples were tested simultaneously with both reagent kits. These include samples from patients evaluated for screening, benign prostatic hyperplasia, and follow-up of prostate cancer. RESULTS: The outcomes of the Hybritech Tandem-R PSA test ranged from 0.0 to 48.3 ng/mL with a median value of 2.4 ng/mL (mean 3.48, SD 5.46). The outcomes of the Abbott AxSYM PSA test ranged from 0.0 to 49.33 ng/mL with a median of 2.22 ng/mL (mean 3.82, SD 5.59). The outcomes of the two assays were found to be highly correlated by the Pearson correlation coefficient (r = 0.9942). When samples were divided according to PSA levels of 0.0 to less than 2.5, 2.5 to less than 4.0, 4.0 to less than 10.0, and 10.0 to less than 25.0 ng/mL, the outcomes were also highly correlated in all PSA level ranges (r = 0.9619, 0.8094, 0.9167, and 0.9081, respectively). CONCLUSIONS: The PSA values of the Tandem-R and Abbott AxSYM assays are highly correlated in the PSA level ranges of 0.0 to less than 2.5, 2.5 to less than 4.0, 4.0 to less than 10.0, and 10.0 to less than 25.0 ng/mL.     

Effects of the purpose of rating on accuracy in observing teacher behavior and evaluating teaching performance.

Previous research has suggested that ratings used to make administrative decisions are lenient when compared with ratings obtained for research purposes only. The present study examined the effects of the purpose of rating on multivariate measures of accuracy in observing teacher behavior as well as measures of accuracy in evaluating teaching performance. 45 undergraduates viewed and evaluated videotaped lectures under conditions in which they were informed that their ratings would be used for research only or for making important decisions about those being rated. The purpose of rating did not affect measures of accuracy in rating the frequency with which a number of critical behaviors occurred on each tape. The purpose of rating also did not affect multivariate measures of performance rating accuracy. Purpose did, however, affect the relationship between accuracy in observing teacher behavior and accuracy in evaluating teaching performance. It is suggested that purpose affects the way in which raters process behavioral information without necessarily affecting the general level of rating. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Issues in evaluating vocational rehabilitation programs.

Addresses issues in the evaluation of vocational rehabilitation (VR) programs for the disabled and discusses examples of 10 common evaluation problems typically encountered in assessing VR services. The usefulness of conducting an initial evaluability assessment is emphasized to identify and deal with potential obstacles to evaluation and to prevent a premature evaluation effort. It is concluded that, in spite of the complexity of carrying out evaluation research, the improvement of VR and other rehabilitation services depends on this program-monitoring and budget-justifying activity. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phytochromes and cryptochromes in the entrainment of the Arabidopsis circadian clock

Circadian clocks are synchronized by environmental cues such as light. Photoreceptor-deficient Arabidopsis thaliana mutants were used to measure the effect of light fluence rate on circadian period in plants. Phytochrome B is the primary high-intensity red light photoreceptor for circadian control, and phytochrome A acts under low-intensity red light. Cryptochrome 1 and phytochrome A both act to transmit low-fluence blue light to the clock. Cryptochrome 1 mediates high-intensity blue light signals for period length control. The presence of cryptochromes in both plants and animals suggests that circadian input pathways have been conserved throughout evolution.