Guiding principles and recommendations for the assessment of competence.

This article presents guiding principles for the assessment of competence developed by the members of the American Psychological Association's Task Force on Assessment of Competence in Professional Psychology. These principles are applicable to the education, training, and credentialing of professional psychologists, and to practicing psychologists across the professional life span. The principles are built upon a review of competency assessment models, including practices in both psychology and other professions. These principles will help to ensure that psychologists reinforce the importance of a culture of competence. The implications of the principles for professional psychology also are highlighted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

HIV type 1 subtypes in Malaysia, determined with serologic assays: 1992-1996

We investigated the molecular epidemiology of HIV-1 subtypes in Malaysia among injecting drug users (IDUs) and sexual transmission risk groups, using serologic and genetic techniques. Frozen sera collected at a general hospital, a blood bank, several drug treatment centers, and an STD clinic in Kuala Lumpur, between 1992 and 1996, were investigated retrospectively. V3 peptide serotyping and monomeric gp120 capture serotyping were used to study 89 known HIV-1-infected subjects. The methods differentiate subtypes B, E, and C. V3 peptide and gp120 capture results were comparable. No subtype C-specific reactive sera were found; one specimen was dually reactive for subtypes C and B, using the V3 peptide ELISA; and four were durally reactive for subtypes E and C using this assay. Genotypic analysis of HIV-1 gag RNA in serum was done on a subset of subjects and confirmed serologic findings. HIV-1 subtypes differed significantly by risk category: of 53 IDUs, 29 (55%) were infected with subtype B and 19 (36%) were infected with subtype E, 3 (6%) were dually reactive, and 2 (4%) were not typable. Of 36 persons with heterosexual risks, 29 (81%) were infected with subtype E, 5 (14%) were infected with subtype B, and 2 (5%) were not typable. Persons with IDU risks were significantly more likely to be infected with subtype B than were those with sexual risks (OR 5.89; 95% CI, 1.94-18.54; p < 0.001). Subtypes B and E of HIV-1 appear to predominate in Malaysia; subtype B was more prevalent among IDUs; subtype E was more prevalent among all other groups. These results may have important HIV-1 vaccine implications.     

Chemical and Biological Assays to Evaluate Bacterial Inhibition by Tannins

The interactions among purified tannins from three different plants with five strains of ruminal bacteria were investigated. Tannins were purified from crude quebracho (Schinopsis balansae spp.), desmodium (Desmodium ovalifolium), and myrtle (Mirtus communis). The ruminal bacteria studied were Streptococcus bovis JB1, Ruminococcus albus 8, Fibrobacter succinogenes S85, Prevotella ruminicola H₁4, and a recently isolated tannin-tolerant bacterium. Bacterial binding to tannins, rate of tannin binding, and the inhibitory concentrations for each bacterium to each tannin were evaluated. The effects of tannins on glucose utilization and fermentation product formation also were studied. Tannin binding was rapid with little additional binding occurring 10 min after tannin addition. There was variation among bacteria in the amount of tannins bound and in the amount of tannin required to inhibit growth. Condensed tannins from myrtle and desmodium had the highest binding capacity and were most inhibitory to microbes. Absorbance readings from the total phenolics assay were highest for myrtle and lowest for quebracho. Similarly, readings for condensed tannins were highest for desmodium, which also had the largest polymer size. Myrtle and quebracho gave the largest precipitate rings in the radial diffusion assay, a biological assay that measures precipitation of bovine serum albumin by tannins. The relative absorbance values obtained from the total phenolics assay were the most useful predictor of tannin inhibition of microbial growth. The acid–butanol assay and the radial diffusion assay using bovine serum albumin as the precipitable protein were much less useful predictors of tannin biological activity against the bacteria studied.     

Dimensionality and clustering in the semantic network of patients with Alzheimer's disease.

Investigated the organization of semantic memory in patients with Alzheimer's disease (AD) with a triadic comparison task. A multidimensional scaling statistic was used to analyze proximity data and to generate 3-dimensional cognitive maps that were then compared by a discriminant function analysis. Results suggest that the structure of semantic memory in AD Ss differs from that of elderly normal controls (NCs) in 2 ways. First, AD Ss are less consistent in using the attributes (predation, domesticity, and size) of concepts. Second, AD Ss focus primarily on concrete perceptual information (size), whereas NCs stress abstract conceptual knowledge (domesticity). Results are consistent with the notion that AD is characterized by a breakdown in the structure of semantic knowledge. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Dihydrobenzofuran analogues of hallucinogens. 3. Models of 4-substituted (2,5-dimethoxyphenyl)alkylamine derivatives with rigidified methoxy groups

Tetrahydrobenzodifuran functionalities were employed as conformationally restricted bioisosteres of the aromatic methoxy groups in prototypical hallucinogenic phenylalkylamines 1 and 2. Thus, a series of 8-substituted 1-(2,3,6,7-tetrahydrobenzo[1,2-b:4,5-b']difuran-4-yl)-2-aminoal kanes (7a-e) were prepared and evaluated for activity in the two-lever drug discrimination paradigm in rats trained to discriminate saline from LSD tartrate (0.08 mg/kg) and for the ability to displace [3H]ketanserin from rat cortical homogenate 5-HT2A receptors and [3H]-8-OH-DPAT from rat hippocampal homogenate 5-HT1A receptors. In addition, 1-(8-bromo-2,3,6,7-tetrahydrobenzo[1,2-b:4,5-b']difuran-4-yl)-2-am inopropane (7b), which was found to be extremely potent in the rat in vivo assays, was evaluated for its ability to compete with [125I]DOI and [3H]ketanserin binding to cells expressing cloned human 5-HT2A, 5-HT2B, and 5-HT2C receptors. All of the dihydrofuranyl compounds having a hydrophobic substituent para to the alkylamine side chain had activities in both the in vitro and in vivo assays that equaled or surpassed the activity of the analogous conformationally flexible parent compounds. For example, 7b substituted for LSD in the drug discrimination assay with an ED50 of 61 nmol/kg and had Kj values in the nanomolar to subnanomolar range for the displacement of radioligand from rat and human 5-HT2 receptors, making it one of the most potent hallucinogen-like phenylalkylamine derivatives reported to date. The results suggest that the dihydrofuran rings in these new analogues effectively model the active binding conformations of the methoxy groups of the parent compounds 1 and 2. In addition, the results provide information about the topography and relative orientation of residues involved in agonist binding in the serotonin 5-HT2 receptors.     

频谱分析的简化IF数字化

通信接收器与频谱分析仪内部信号链路的架构之间存在着相似性。利用功能强大的数字信号处理器（DSP），先进的数字接收器可在数字域中（而不像过去的产品那样在模拟域中）进行同相和正交（I-Q）信息的解调。虽然通信接收器连续执行载频和符号时钟恢复，但频谱分析仪则以“字组”的形式来捕获该信息，并以时点的方式进行存储，     

Delaying interference enhances memory consolidation in amnesic patients.

Some patients with amnesia are able to retain new information for much longer than expected when the time that follows new learning is devoid of further stimuli. Animal work shows that the absence or delaying of interference improves long-term memory consolidation. Our study suggests that this is also true for at least some patients with amnesia. Retention of new verbal material was significantly higher in a sample of patients with amnesia (N = 12) when interference occurred at the end of a 9-min delay interval than when it occurred in the middle or at the beginning of the interval. Such findings cannot be accounted for by the mere use of explicit short-term memory rehearsal. Any such rehearsal should have been blocked by the interference, irrespective of interference onset, thus leading to poor retention in all three conditions. The current findings suggest that at least some of the severe forgetting observed in amnesia is the product of a disruption of memory consolidation by immediate postlearning interference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)