Source apportionment of polycyclic aromatic hydrocarbons in New York/New Jersey Harbour sediment

Data on polycyclic aromatic hydrocarbons (PAHs) measured in surface sediment and cores in the New York/New Jersey Harbour under the Contamination Assessment and Reduction Project (CARP) was examined via Positive Matrix Factorization (PMF), which revealed six sources. Two represented the higher and lower molecular weight (MW) fractions of coal tar and/or creosote (pyrogenic) sources and explained 49% of PAH mass in the sediment samples. Two sources were related to uncombusted petroleum (petrogenic) sources, such as heavy fuel oil and crude oil, and explained 30% of PAH mass. The final two sources were related to combustion (pyrogenic) sources such as gasoline- and diesel-fuelled vehicles and explained 21% of the PAH mass. Sediment cores revealed that Σ₂₂PAH increased from the pre-industrial period until about 1980 and then decreased because of efforts to control water pollution via mechanisms such as the Clean Water Act.     

Light induced Nitrosomonas inhibition

The purpose of this study was to evaluate and verify the impact of light exposure on an enriched Nitrosomonas culture. Resting cells maintained under aerobic conditions without an exogenous ammonium-nitrogen source were fully inhibited within a 10 min period of ambient light contact (i.e. fluorescent and indirect natural room light). These cells were, however, protected against this inhibitive phenomenon during active respiration periods and during anoxic exposure conditions. Recovery, albiet partial, from such light induced inhibition was initiated after a “dark” contact period of approx. 2.5–3 h without exogenous ammonium presence. Research involving enriched or pure Nitrosomonas cultures (e.g. batch bioassay testing) should consequently be completed under environmental conditions designed to obviate this problem.     

The Consumer Reports study of psychotherapy: Invalid is invalid.

Contends that M. E. P. Seligman's (see record 1996-13324-001) reanalysis of the Consumer Reports survey does not warrant any new conclusions about the effectiveness of psychotherapy. Several methodological flaws are also noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An investigation of the Color-Your-Life technique with childhood cancer patients.

Assessed how children with cancer use the Color-Your-Life (CYL) technique and compared the results to K. J. O'Connor's (1983) clinical impressions of this technique. 20 cancer patients and 20 healthy students (aged 6–12 yrs) completed the study. Ss were given a piece of white paper and a standard box of 8 crayons. A chart was displayed that listed the 8 colors and the specific feelings that corresponded with that color. Ss were told that the paper represented their lives and that they should use the colors that represented the feelings they had in their lives. Findings show differences in the styles of drawing, percentages of color/feeling represented in the drawings, and percentage of white space between pediatric Ss with cancer and control Ss. Findings are consistent with O'Conner's findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A problem with the interpretation of before-and-after experiments of drug tolerance.

Four groups of amygdala-kindled rats were exposed lo 15 daily tolerance-development trials. On each trial, 1 group received diazepam (2.5 mg/kg IP) 1 hr before a convulsive stimulation, 1 group received diazepam 1 hr after a stimulation, 1 group received 15 diazepam injections but no stimulation, and a combined control group received 15 vehicle injections either with or without a stimulation. Consistent with previous findings, only subjects that had received diazepam before the stimulations during the tolerance-development phase displayed significant tolerance to diazepam's anticonvulsant effect on the first test trial. The major new finding was that diazepam injections by themselves induced significant savings (i.e., residual tolerance) on the test trials but that diazopam injections preceded by convulsive stimulations did not. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prefrontal cognitive processes: Working memory and inhibition in the antisaccade task.

Recent research suggests 2 principal processes are assessed in many neuropsychological tests of prefrontal functioning: the ability to keep transient information on-line (working memory) and the ability to inhibit prepotent, but incorrect, responses. The current studies examined the hypothesis that taxing working memory beyond some threshold can result in decreased inhibition, resembling the errors committed by patients with prefrontal dysfunctions. Across 3 studies, 70 nonpatient subjects were tested on the antisaccade (AS) task (D. Guitton et al, 1985)—a task sensitive to inhibitory deficits. Subjects were required to look in the opposite direction of a flashed cue, inhibiting the reflexive tendency to saccade to the cue. Subjects performed concurrent tasks that varied working-memory load. The results indicated that conditions with the highest working-memory load produced inhibitory errors comparable to patients with prefrontal dysfunctions. The findings are discussed in terms of the interaction between working memory and the inhibition of prepotent responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fine Structure in NMR Correlation Spectroscopy

A simplified treatment of two-dimensional homonuclear correlation spectroscopy (COSY) is proposed, based on a vector model and a consideration of the disturbance of energy level populations caused by the pulse sequence. It predicts the properties of diagonal and crosspeaks in the same manner as the more rigorous product operator treatment. Methods of studying the fine structure of COSY crosspeaks are discussed with a particular emphasis on the extraction of coupling constants when the splittings are poorly resolved. Three new schemes are described for the accurate measurement of couplings; they are called “J-extension”, “J-deconvolution”, and “J-doubling”. All three rely on processing the experimental time-domain signals with simple trigonometrical functions, followed by Fourier transformation. The J-deconvolution and J-doubling methods lend themselves to automated analysis by computer. These procedures can be applied to either active or passive couplings and yield an accuracy of ±0.04 Hz in the cases studied. J-deconvolution may be implemented repetitively in order to reduce a COSY crosspeak to a single absorption peak at the chemical shift coordinates.     

Teacher preferences for service delivery: A look at attribution research.

Reviews the literature on teacher attributions and discusses the relevance of causal attributions to teacher preferences for service delivery (i.e., referral for psychoeducational assessment, consultation). Literature is reviewed in the context of B. Weiner's (see record 1979-28688-001) proposed dimensions of causality. In addition, practical implications for this literature are discussed, and future research endeavors exploring the relationship between causal attributions and preferences for service delivery are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Esters of L-dopa: structure-hydrolysis relationships and ability to induce circling behaviour in an experimental model of hemiparkinsonism

A number of carboxylate esters of L-dopa, some of which are novel, were examined for their physicochemical and biological properties. A few esters of tyrosine and phenylalanine were included for comparison. The compounds displayed great differences in their lipophilicity and stability towards chemical and enzymatic (human plasma) hydrolysis. Within subseries, relationships exist between structural properties and rate constants of chemical or enzymatic hydrolysis. In an experimental model of hemiparkinsonism (circling behaviour in rats), some of the L-dopa esters (the isopropyl, sec-butyl and 2-(tetrahydropyranyl)methyl esters) showed an activity distinctly greater than that of L-dopa, although the difference was not statistically significant.