Use of flow-normalization to evaluate nutrient concentration and flux changes in Lake Champlain tributaries, 1990–2009

The U.S. Geological Survey evaluated 20 years of total phosphorus (P) and total nitrogen (N) concentration data for 18 Lake Champlain tributaries using a new statistical method based on weighted regressions to estimate daily concentration and flux histories based on discharge, season, and trend as explanatory variables. The use of all the streamflow discharge values for a given date in the record, in a process called “flow-normalization”, removed the year-to-year variation due to streamflow and generated a smooth time series from which trends were calculated. This approach to data analysis can be of great value to evaluations of the success of restoration efforts because it filters out the large random fluctuations in the flux that are due to the temporal variability in streamflow. Results for the full 20 years of record showed a mixture of upward and downward trends for concentrations and yields of P and N. When the record was broken into two 10-year periods, for many tributaries, the more recent period showed a reversal in N from upward to downward trends and a similar reversal or reduction in magnitude of upward trends for P. Some measures of P and N concentrations and yields appear to be related to intensity of agricultural activities, point-source loads of P, or population density. Total flow-normalized P flux aggregated from the monitored tributaries showed a decrease of 30 metric tons per year from 1991 to 2009, which is about 15% of the targeted reduction established by the operational management plan for the Lake Champlain Basin.     

The validity of the desired effects of drinking scale with a late adolescent sample.

This study evaluated the validity of the Desired Effects of Drinking Scale (DEoDS) with a late adolescent sample. This brief measure (37 items) was designed to assess reasons for drinking across 9 domains. Across a culturally diverse sample of late adolescents (ages 18-20 years), this measure evidenced high internal consistency, particularly when all items were summed in 1 full-scale score. Contrary to the factors found with adults, 8 factors emerged with this sample. No differences were found by culture, providing initial evidence for the cross-cultural validity of this measure. In addition, gender differences emerged for only 1 factor. Overall, the results provide empirical support for the use of this measure to assess late adolescents' and emerging adults' reasons for drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nicotine decreases attentional bias to negative-affect-related Stroop words among smokers

The present study examined the hypothesis that nicotine is associated with reduced attentional bias to affective and smoking-related stimuli in a modified Stroop task. A total of 56 habitual smokers were each tested on 4 days with 14 mg nicotine patches and placebo patches, counterbalanced, as a within-subjects factor in a double-blind design. A modified Stroop using negative-affect words, smoking words, color words, and neutral words was presented via computer in blocked format. As predicted, nicotine, relative to placebo, was associated with decreased attentional bias to negative words. Nicotine speeded performance during smoking-word and color-word blocks to the same degree as during neutral words and thus appeared to also have a nonspecific performance-enhancing effect. In an exploratory analysis, nicotine-attention effects occurred only in the initial presentation of pairs of blocked word pages. Nicotine also was associated with improved mood. The results are discussed in terms of affect-attention and smoking literatures.     

Alumina-pillared clays and their adsorptive properties.

This work has explored the synthesis of alumina-pillared montmorillonite and Laponite. The importance of stoichiometry has been examined. A zirconia-pillared montmorillonite is also reported. All these products are fully characterised by X-ray diffraction and by the adsorption of nitrogen, water, n-butane, methanol, and neo-pentane. The implications for the real microstructures of these materials are discussed.     

Book reviews

The preparation of this review was supported by a training grant from NIH (DC #00036).     

Development of an operant-based taxonomy and observational index of supervisory behavior.

The Operant Supervisory Taxonomy and Index (OSTI), a theory-based taxonomy and observational instrument of supervisory behavior, includes 7 categories of supervisory behavior, the 1st 3 of which are based on the theory of operant conditioning and considered to be related to effective supervision: performance consequences, performance monitors, performance antecedents, one's own performance, work-related, non-work-related, and solitary. Field tests of the OSTI, which consisted of 189 30-min observations of 7 theater managers over a 5-wk period and 440 30-min observations of 20 bank managers over a 12-wk period, showed that the OSTI was feasible, acceptably reliable, and sensitive to differences in behavior among managers. A generalizability theory analysis indicated that 20 30-min observations provided reasonably representative information on a given manager's behavior. (44 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Low-Temperature Crystallization of Sol-Gel Processed Pb0.5Ba0.5TiO3: Powders and Oriented Thin Films

A novel sol-gel process suitable for depositing thin-film lead barium titanate has been developed. X-ray diffraction analysis showed perovskite phase crystallization to occur at a temperature as low as 400°C with single-phase Pb_0.5Ba_0.5TiO₃ (PBT) resulting at a temperature as low as 500°C. Small concentrations of barium carbonate were evident by X-ray diffraction at 400°C, and indications of minor, carbonate-containing phases were evident by FTIR at 600°C. Deposition of the sol by spin coating on single-crystal and thin-film MgO on silicon resulted in highly oriented PBT films after calcination at 600°C. Mixed (100)/(001) films were obtained on single-crystal MgO, whereas entirely (100) films were obtained on thin-film MgO.     

A collection of experimental data for aerosol monitoring cyclones

Cyclone behavior is complex and difficult to model. Recent years have seen the development of new and better predictive models for cyclone performance, which are providing new insights into how cyclone performance is affected by cyclone geometry. Experimental data are essential for verification of such models. In this article we present a dataset of more than 250 experimental determinations of cyclone penetration. The dataset includes cyclones with a wide range of sizes and geometries, tested at a wide range of flow rates. We illustrate some empirical, semi-empirical and mathematical approaches to modeling these cyclone data. For our data, we show that mathematical modeling approaches developed for large gas-cleaning cyclones can also be applied to small aerosol monitoring cyclones, to diverse cyclone geometries, and laminar flow operating conditions.

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