Alternate and new brominated flame retardants detected in U.S. house dust

Due to the voluntary withdrawals and/or bans on the use of two polybrominated diphenyl ether (PBDE) commercial mixtures, an increasing number of alternate flame retardant chemicals are being introduced in commercial applications. To determine if these alternate BFRs are present in indoor environments, we analyzed dust samples collected from 19 homes in the greater Boston, MA area during 2006. Using pure and commercial standards we quantified the following brominated flame retardant chemicals using GC/ECNI-MS methods: hexabromocyclododecane (sigma HBCD), bis(2,4,6,-tribromphenoxy)ethane (BTBPE), decabromodiphenyl ethane (DBDPE), and the brominated components found in Firemaster 550 (FM 550): 2-ethylhexyl 2,3,4,5-tetrabromobenzoate (TBB) and (2-ethylhexyl)tetrabromophthalate (TBPH), the latter compound being a brominated analogue of di(2-ethylhexyl)phthalate (DEHP). The concentrations of all compounds were log-normally distributed and the largest range in concentrations was observed for HBCD (sum of all isomers), with concentrations ranging from <4.5 ng/g to a maximum of 130,200 ng/g with a median value of 230 ng/g. BTBPE ranged from 1.6 to 789 ng/g with a median value of 30 ng/g and DBDPE ranged from <10.0 to 11,070 ng/g with a median value of 201 ng/g. Of the FM 550 components, TBB ranged from <6.6 to 15,030 ng/g with a median value of 133 ng/g; whereas TBPH ranged from 1.5 to 10,630 ng/g with a median value of 142 ng/g. Furthermore, the ratio of TBB/TBPH present in the dust samples ranged from 0.05 to 50 (average 4.4), varying considerably from the ratio observed in the FM 550 commercial mixture (4:1 by mass), suggesting different sources with different chemical compositions, and/or differential fate and transport within the home. Analysis of paired dust samples collected from different rooms in the same home suggests HBCD, TBB, and TBPH are higher in dust from the main living area compared to dust collected in bedrooms; however, BTBPE and DBDPE levels were comparable between rooms. This study highlights the fact that numerous types of brominated flame retardants are present in indoor environments, raising questions about exposure to mixtures of these contaminants.     

Vectors and gene targeting modules for tandem affinity purification in Schizosaccharomyces pombe

We describe the construction of tagging cassettes and plasmids for tandem affinity purification (TAP) of proteins in Schizosaccharomyces pombe. The tagging cassettes are designed for either carboxy- or amino-terminal tagging of proteins. The carboxyl terminal tags differ in that they contain either two or four repeats of IgG binding units. For tagging endogenous loci, the cassettes contain the kan MX6 module to allow for selection of G418-resistant cells. The amino-terminal tagging vectors allow for the regulated expression of proteins. Sz. pombe Cdc2p was chosen to test these new affinity tags. Several known binding proteins co-purified with both Cdc2p-CTAP and N-TAP-Cdc2p, indicating the usefulness of these tags for the rapid purification of stable protein complexes from Sz. pombe.     

The impact of river regulation and climate change on the barred estuary of the Oued Massa,southern Morocco

The estuary of the Oued Massa, southern Morocco, has experienced alternating phases of tidal and lagoon conditions. Using field surveys, aerial photographs and rainfall–runoff records the dominant processes and recent evolution of the estuary are described. These data suggest that the character of the estuary has changed since the upstream impoundment of the river by the Youssef Ben Tachfine reservoir. The frequency of low‐flows has been significantly increased by river regulation, as has the mean interval between flood events. Using reconstructed flow series it is speculated that lagoon conditions have become more common in the post‐impoundment era than at any time since the 1920s. Although increases in winter precipitation projected by the global climate model HadCM2 for 2030–2049 imply a higher frequency of flood flows entering the reservoir in the future, the magnitude and frequency of such inflows are still within historic variability. Nonetheless, higher inflows may produce more frequent spills with concomitant bar breaching and termination of lagoon phases. Despite this, it is argued that the presence of the dam is ultimately of greater consequence to the functioning of the estuary–lagoon system than future precipitation changes over the region. Copyright © 2001 John Wiley & Sons, Ltd.     

Rating formats and rater training redux: A context-specific approach for enhancing the effectiveness of performance management.

In this paper, we critically examine previous research on rating formats and rater training in the context of performance appraisal. Historically, the goal of this body of research has been to search for ways of maximizing the psychometric quality of performance evaluation data. Our central thesis is that there are a number of avenues for broadening this research. Accordingly, we propose a conceptual model that hopefully serves as a conceptual framework for future work in these 2 traditional performance appraisal research streams. For example, both rating formats and rater training research may be useful for facilitating and improving the feedback and employee development process, as well as reducing the potential existence of rater biases. In addition, format and training research may focus upon ways of enhancing both rater and ratee reactions to the appraisal system. A key feature of our model is the integration of national culture as a moderator of the relations between specific formats, training programs, and various outcomes. We consider both the national culture of raters and ratees, and focus specifically on comparisons between Western and East Asian cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recovering Reasoning Processes from User Interactions

Understanding how analysts use visual-analytics (VA) tools can help reveal their reasoning processes when using these tools. By examining analysts' interaction logs, the authors identified the analysts' strategies, methods, and findings when using a financial VA tool.     

Firm Partial Modularity and Performance in the Electronic Manufacturing Services Industry

Firms continue to develop new ways to decentralize non-core activities to outside parties. Scholars have approached this issue with modularity theory, suggesting a continuum of arrangements ranging from hierarchy to market. Hierarchy relies on fiat, while partially modular forms, those forms between hierarchy and market, require greater coordination, communication and relationships between firms than do fully modular (or market) forms. While modularity theory identifies this continuum, the associated empirical literature tends to dichotomize modularity: firms are either modular or they are not. Nor does the empirical literature examine the performance outcomes of modular arrangements within this continuum. By examining firms that vary between full integration and partial modularity with a continuous modularity measure, this paper empirically examines the performance outcomes associated with a range of modularity levels. We derive this measure from a peculiar inventory option available within the electronic manufacturing services (EMS) industry. Our data include observations on 260 firms over five years. We find that more firms rely on partially modular arrangements, the lower their performance. We suggest explanations for this result, and areas of future research meant to pursue it.     

Designing safe job rotation schedules using optimization and heuristic search

Job rotation is one method that is sometimes used to reduce exposure to strenuous materials handling; however, developing effective rotation schedules can be complex in even moderate sized facilities. The purpose of this research is to develop methods of incorporating safety criteria into scheduling algorithms to produce job rotation schedules that reduce the potential for injury. Integer programming and a genetic algorithm were used to construct job rotation schedules. Schedules were comprised of lifting tasks whose potential for causing injury was assessed with the Job Severity Index. Each method was used to design four job rotation schedules that met specified safety criteria in a working environment where the object weight, horizontal distance and repetition rate varied over time. Each rotation was assigned to a specific gender/lifting capacity group. Five versions of the integer programming search method were applied to this problem. Each version generated one job rotation schedule. The genetic algorithm model was able to create a population of 437 feasible solutions to the rotation problem. Utilizing cluster analysis, a rule set was derived from the genetic algorithm generated solutions. These rules provided guidelines for designing safe job rotation schedules without the use of a computer. The advantages and limitations of these approaches in developing administrative controls for the prevention of back injury are discussed.     

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