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The mechanism for enhanced desorption of chloroaliphatic compounds from a silty loam soil by modified Fenton's reagent was investigated using a series of probe compounds of varying hydrophobicities. Hexachloroethane, which has negligible reactivity with hydroxyl radicals, was transformed more rapidly in modified Fenton's reactions (g0.3 M hydrogen peroxide) than it was lost by gas-purge desorption, suggesting the existence of a non-hydroxyl radical mechanism. The addition of excess 2-propanol to scavenge hydroxyl radicals slowed, but did not stop, the desorption and degradation of hexachloroethane. In the presence of the reductant scavenger chloroform, hexachloroethane did not desorb and was not degraded, indicating that a reductive pathway in vigorous Fenton-like reactions is responsible for enhanced contaminant desorption. Fenton-like degradation of hexachloroethane yielded the reduced product pentachloroethane, confirming the presence of a reductive mechanism. In the presence of excess 2-propanol, toluene, which has negligible reactivity with reductants, was displaced from the soil but not degraded. The results are consistent with enhanced contaminant desorption by reductants, followed by oxidation and reduction in the aqueous phase. Vigorous Fentonlike reactions in which reductants and hydroxyl radicals are generated may provide a universal treatment matrix in which contaminants are desorbed and then oxidized and reduced in a single system.

A reliability generalization study (a meta-analysis of reliability coefficients) was conducted on three widely studied information systems constructs from the technology acceptance model (TAM): perceived ease of use, perceived usefulness, and behavioral intentions. This form of meta-analysis summarizes the reliability coefficients of the scores on a specified scale across studies and identifies the study characteristics that influence the reliability of these scores. Reliability is a critical issue in conducting empirical research as the reliability of the scores on well-established scales can vary with study characteristics, attenuating effect sizes. In conducting this study, an extensive literature search was conducted, with 380 articles reviewed and coded to perform reliability generalization. Study characteristics, including technology, sample, and measurement characteristics, for these articles were recorded along with effect size data for the relationships among these variables. After controlling for number of items, sample size, and sampling error, differences in reliability coefficients were found with several study characteristics for the three technology acceptance constructs. The reliability coefficients of PEOU and PU were lower in hedonic contexts than in utilitarian contexts, and were higher when the originally validated scales were used as compared to when other items were substituted. Only 27 percent of the studies that provided the measurement items used the original PEOU items, while 39 percent used the original PU items. Scales that were administered in English had higher reliability coefficients for PU and BI, with a marginal effect for PEOU. Reliability differences were also found for other study characteristics, including reliability type, subject experience, and gender composition. While average reliability coefficients were high, the results show that, on average, relationships among these constructs are attenuated by 12 percent with maximum attenuation in the range of 35 to 43 percent. Implications for technology acceptance research are discussed and suggestions for addressing variation in reliability coefficients across studies are provided.

Interfaces now employ a variety of media-rich, social, and advanced decision-making components, including recommendation agents (RA) designed to assist users with their tasks. Social presence has been identified as a key consideration in website design to overcome the lack of warmth, social cues, and face-to-face interaction, but few studies have investigated the interface features that may increase social presence. Recent research on RAs has similarly acknowledged social presence as a key factor in the design of online RAs and in building trust in this technology, but there has been limited empirical work on the topic. In this study an experiment was conducted to explore how social technology cues, media capabilities, and individual differences influence social presence and trust in an RA. RA personality (extraversion), vividness (text, voice, and animation), and computer playfulness were found to influence social presence, with social presence serving in a mediating role and increasing user trust in the RA. Vividness also had a moderating effect on the relationship between RA extraversion and social presence such that increased levels of vividness strengthen this relationship.

Enhanced biological phosphorus removal (EBPR) is a well-established technology for removing phosphorus from wastewater. However, the process remains operationally unstable in many systems, primarily because there is a lack of understanding regarding the microbiology of EBPR. This paper presents a review of advances made in the study of EBPR microbiology and focuses on the identification, enrichment, classification, morphology, and metabolic capacity of polyphosphate-and glycogen-accumulating organisms. The paper also highlights knowledge gaps and research challenges in the field of EBPR microbiology. Based on the review, the following recommendations regarding the future direction of EBPR microbial research were developed: (1) shifting from a reductionist approach to a more holistic system-based approach, (2) using a combination of culture-dependent and cultureindependent techniques in characterizing microbial composition, (3) integrating ecological principles into system design to enhance stability, and (4) reexamining current theoretical explanations of why and how EBPR occurs. Water Environ. Res., 83, 195 (2011).

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This study examines how visualization and interactivity affect accuracy, confidence, and calibration in a financial decisionmaking context. Decision-makers are typically overconfident and this research proposes that visualization and interactivity can reduce calibration, increasing overconfidence. An experiment was conducted with 157 participants and the results showed that visualization and interactivity features can increase decision-maker confidence independently. However, interactive visualization, both interface features, are required to increase accuracy. As a result, when interactivity and visualization are offered individually, decision-makers become overconfident, less calibrated. Implications for designers are discussed.

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