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Local implementation of science reform efforts in part relies on science teacher leaders (STLs) to improve science instruction in classrooms and beyond. The lack of science‐specific professional learning resources drives STLs to act as boundary spanners to locate resources outside their local context to fill that gap. Museums and other informal science education centers are examples of external entities that STLs might leverage to locate resources for local science education improvement. While we know how museums support pre‐ and in‐service science teachers, there is a gap in our understanding related to museum support for STLs. Here, we used case study research methods to analyze how a museum‐based professional learning programme supported STLs, as boundary spanners to access and adapt resources for local science education reform efforts. We found that each STL reported benefiting from shared resources from the museum, as well as from their peers in their working groups. We also found that STLs reported on different elements of the professional learning programme related to their area of influence (classroom or district) and the problem of practice their group worked on. We discuss how each of the named features of the museum‐based professional learning programme supported boundary spanning of STLs and end with implications and recommendations for the design of professional learning experiences to support their leadership work. [ABSTRACT FROM AUTHOR]

Soil scientists have worked on the conceptualization and contextualization of soil-related notions, such as soil quality, soil health, and soil security, over the past few decades. We reviewed the massive amount of literature regarding those major concepts, and summarized definitions, visions, and constraints. Indicators (In) and indices (Ix) are well suited to aggregate soil and environmental data to assess soil quality, health, and security quantitatively. Our literature review showed that (i) more sophisticated quantification methods are necessary; (ii) often only a single soil property and/or class is modeled rather than more complex soil functions, risks, or services; (iii) there is a lack of harmonization, standardization, and reference frameworks that allow soil comparisons across regions and time; and (iv) methods frequently used to calculate soil In/Ix, such as ordination and factor analysis, do not consider rigorous axiomatic criteria of scientific sound indication systems. In summary, the complex soil concepts stand in sharp contrast to the applied indication methods in the soil science discipline. We investigated the potential to apply econometrical methods to assess soil quality, health, and security that serve as alternatives to more traditional In/Ix in soil science. A case study demonstrated the profound transformative potential of linking econometrics-soil-environmental sciences. [ABSTRACT FROM AUTHOR]

The literature examining the impact of teachers unions on education is very large and diverse. We meta-analyze the literature on the wage impacts of teachers unions to try to draw out general findings, the importance of empirical model specification, and samples. A key finding of this study is that the average wage impact estimated by the included papers is modest, around 2%-4.5%. Our findings also suggest that the quality of an empirical strategy significantly affects the size of the estimated impact. We find that teachers union wage impacts have varied over time. The largest impacts appear to be following the rapid expansion of teacher unionism in the 1970s. Finally, we gain new insight into the goals of teachers unions by using the increased statistical power of meta-analytic techniques to show that unions increase the wages of new teachers and not just senior teachers. ( JEL J51, I21, I30) [ABSTRACT FROM AUTHOR]

Saturated and unsaturated fluorotelomer carboxylic acids (fluorotelomer acids: FTAs) represent important intermediates in the degradation of fluorotelomer alcohols to perfluorinated carboxylic acids (PFCAs). Recent studies have detected FTAs at low concentrations (ng/L) in precipitation and surface waters; however, information regarding chronic toxicity is lacking. The present study assessed the chronic toxicity of the 8:2 saturated fluorotelomer carboxylic acid (8:2 FTCA) to Chironomus dilutus and the 10:2 saturated and unsaturated fluorotelomer carboxylic acids (10:2 FTCA and 10:2 fluorotelomer unsaturated carboxylic acid [FTuCA]) to Daphnia magna in separate life-cycle tests. In D. magna tests the FTCA was consistently more toxic than the FTuCA. Lethal concentrations (LC50s) were 150 and >60 µg/L for FTuCA and FTCA, respectively. Reproduction was significantly reduced relative to the controls, with respective median effective concentrations (EC50s) for time to first brood and mean number of offspring/female of 287 and 214 µg/L for FTuCA and 50 and 48 µg/L for FTCA. In tests with C. dilutus, EC50s for survival and growth at 20 d were 2,610 and 1,250 µg/L. Total emergence and time to first emergence, the most sensitive endpoints, yielded EC50s of 440 and 890 µg/L. Few adults emerged and no reproduction occurred at the two highest concentrations (600 and 1540 µg/L). Mean number of eggs/female was not affected. These results represent the first chronic toxicity data for FTCAs and additional evidence that FTCAs are more toxic than some PFCAs. While the results indicate that current environmental concentrations of FTAs likely pose negligible risk to aquatic biota, additional quantification of FTAs in surface waters and assessment of their toxicity is needed before meaningful assessments of potential risks to aquatic biota are possible. Environ. Toxicol. Chem. 2010;29:1123–1131. © 2010 SETAC [ABSTRACT FROM AUTHOR]

A letter to the editor is presented about the functional analysis of protein Z and protein Z-dependent protease inhibitor polymorphisms.